Push Start button?

[BumbleDs]

I hope so, but having 2 FOBS could be a pain. What have you figured out yet?

[THUMPER20X]

As long as you have the key fob in ur pocket it will start. I think it has to be 4 feet radius for the car to know the key is there.

[2SSRS@Gen5diy]

Originally Posted by THUMPER20X

As long as you have the key fob in ur pocket it will start. I think it has to be 4 feet radius for the car to know the key is there.

Can i ask how you know this, No disrespect it will help to understand how it works on the car.

[BumbleDs]

I would assume theres a computer somewhere-or reciever that picks up the signal from the FOB-telling the ignition its OK to start. In the STS I had, I believe it was in the touchscreen-I dont know about the Corvette. Are you wanting to completly remove the use of the key in the ignition? With the unit you bought I think thats the only way. I leave to for duty tomorrow and I will talk to our Shop Chief.

[THUMPER20X]

Originally Posted by 2SSRS

Can i ask how you know this, No disrespect it will help to understand how it works on the car.

Just like a smart key on a Lexus, Infiniti theres a short range transmitter in the Fob. it knows where the key is. If you kill the battery in the fob and try start the car it wont run because of the signal from the key fob isnt there.

[THUMPER20X]

The ignition key contains electronics in the key head that receive
energy from the controller module. Upon receipt of the data from the
controller module, the key transmits a unique code through low
frequency transmission. The controller module translates the received
signal from the key into a digital signal which is transmitted to the
body control module (BCM). The received signal is compared to an
internally stored value by the BCM. If the values match, the key is
recognized as valid and a vehicle security password is transmitted
through data link to the engine control module to enable fuel and
starting of the vehicle.


etc etc, re PassKey III

[2SSRS@Gen5diy]

Originally Posted by THUMPER20X

Just like a smart key on a Lexus, Infiniti theres a short range transmitter in the Fob. it knows where the key is. If you kill the battery in the fob and try start the car it wont run because of the signal from the key fob isnt there.

I removed the battery in the fob and put it in the ignition and started the car, There was no problems i did 4 times.

[WorldClassRS]

The Corvette has 4 antennas to guage the position of the key fob. When the fob is sensed in the vehicle and the start swich is depressed the RCDLR/BCM send a security message to The ECM allowing fuel and starter enable. It is an entirely different set up from a keyed ignition vehicle. The transponder in the camaro key is in the transmitter and does not get power from the key fob battery. The antenna for the key transponder is around the lock cylinder. So it will start with a dead fob battery. Teh Camaro and current Corvette have 2 totally different electrical architechtures and most components probably are not compatible.

[WorldClassRS]

xTooltipElement
Service Information
2010 Chevrolet Camaro | Camaro (VIN F)Service Manual | Engine | Engine Controls and Fuel - 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L | Description and Operation | Document ID: 2218083
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Immobilizer Description and Operation
The immobilizer system functions are provided by the body control module (BCM) and the engine control module (ECM), as well as any modules which store and report the security code.

When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coil surrounding the ignition lock cylinder. This exciter coil is part of the theft deterrent module. The energized transponder transmits a signal that contains its unique value, which is received by the BCM. The BCM then compares this value to a value stored in memory. The BCM also monitors various modules to determine that the stored security code matches.

If the both the security code and the value received from the transponder match, the BCM will send the prerelease password via serial data to the ECM. If the transponders unique value is incorrect or the security code does not match, the BCM will send the fuel disable message to the ECM.

When the ECM receives the BCM prerelease password, the ECM will challenge the password. The ECM sends this challenge back to the BCM via serial data. Both the ECM and BCM perform a calculation on this challenge. If the calculated response from the BCM equals the calculation performed by the ECM, the ECM will allow vehicle starting.

The components of the theft system are as follows:

• BCM

• ECM

• Theft deterrent module

• Ignition key (Transponder)

• Security indicator

• Various modules which store and report the security code

Body Control Module (BCM)
The immobilizer system is an integral part of the BCM and is controlled internally within the BCM. The BCM can learn up to 8 keys (transponder values).

The BCM uses the following inputs:

• Security code exchange with various modules

• Transponder identification from theft deterrent module

The BCM uses the following outputs:

• Prerelease password communication with ECM

• Challenge/response with ECM

When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coils surrounding the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value, which is received by the BCM. The BCM then compares this value to the learned key code stored in memory. The BCM then performs one of the following functions:

• If the transponder value matches the values stored in the BCM memory, the BCM will send the prerelease password to the ECM via serial data.

• If the transponders unique value does not match the value stored in the BCM, the BCM will send the start disable message to the ECM via serial data.

• If the BCM is unable to measure the ignition key transponder value, the BCM will not send any messages to the ECM.

Engine Control Module (ECM)
When the ECM receives the BCM prerelease password, the ECM will challenge the password. The ECM sends this challenge back to the BCM via the serial data circuit. Both the ECM and BCM perform a calculation on this challenge. If the calculated response from the BCM equals the calculation performed by the ECM, the ECM will allow vehicle starting.

The ECM will disable vehicle starting if any of the following conditions occur:

• The prerelease password is invalid.

• The start disable password is sent by the BCM.

• No passwords are received. There is no communication with the BCM.

• The BCM calculated response to the challenge does not equal the calculation performed by the ECM.

Theft Deterrent Module
The theft deterrent module contains an exciter coil which surrounds the ignition cylinder. The exciter passively powers the transponder located in the ignition key when the key is in the ignition. When powered, the transponder transmits its unique value to the theft deterrent module, which is then relayed to the BCM via a LIN serial data circuit. The theft deterrent module also receives B+ and ground from the BCM.

The Ignition Key (Transponder)
The ignition key for PassKey III+ (PK3+) equipped vehicles is a standard ignition key with a transponder located in the plastic head of the key. The transponder value is fixed and unable to be changed. The immobilizer system uses the ignition key transponder value to determine if a valid ignition key is being used to start the vehicle. There are approximately 3 trillion possible transponder values. There are no visible electrical contacts. The keys are identified by + symbol in a circle stamped into the steel shank of the key.

Security Code
Various modules throughout the vehicle learn a specific security code during the module programming process. The security code learned by each individual module matches the security code stored in the BCM, which is the security code master. Prior to starting, each of the modules which store a security code will compare their code to that of the code stored in the BCM. If all the codes match, the engine starting process will continue. If the security codes do not match, engine starting will be disabled.

Security Indicator
The BCM will command the instrument panel cluster to illuminate the security indicator when the ignition key is in the ON position to indicate a fault is noted in the immobilizer system and when the engine starting is disabled.
© 2009 General Motors Corporation. All rights reserved.

[WorldClassRS]

xTooltipElement
Service Information
2010 Chevrolet Corvette | Corvette (VIN Y) Service Manual | Safety and Security | Immobilizer | Description and Operation | Document ID: 1911419
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Immobilizer Description and Operation
Immobilizer System
The immobilizer system is incorporated into the remote control door lock receiver (RCDLR). The immobilizer is provided in order to prevent the vehicle operation if an incorrect or unprogrammed keyless entry transmitter is used in an attempt to start the vehicle. When the ignition button is pressed, the backup keyless entry antenna broadcasts a challenge to the transmitter. Both the RCDLR and the transmitter perform a calculation based on this challenge. The transmitter will transmit its calculation result to the RCDLR via radio frequency (RF). If both calculations match, vehicle starting will be allowed. This is accomplished by the RCDLR sending a fuel enable message to the engine control module (ECM).

The design of the immobilizer system is to prevent vehicle theft by disabling the engine unless the correct transmitter is present when attempting to start the vehicle. The system is similar in concept to conventional immobilizer system which use a normal vehicle key. The components of the immobilizer system are as follows:

• The start button

• The #1-#4 keyless entry transmitters

• The backup keyless entry antenna

• The body control module (BCM)

• The RCDLR

• The security indicator

• The ECM

Start Button
The start button is located at the right side of the steering column, on the instrument panel. The start button is used to start the vehicle engine, turn OFF the vehicle, put the vehicle in ACC mode, or put the vehicle in RUN mode.

The start button signals the body control module (BCM) to ground the Run/Crank control relay which will then feed power to the Crank relay in the under hood fuse block. The BCM also simultaneously send a serial data message to the engine control module (ECM) to ground the starter enable relay to allow power to the starter solenoid and starter motor.

Keyless Entry Transmitters
The keyless entry transmitters are not only used to passively or actively lock and unlock the vehicle, they are also used to allow vehicle starting. If the remote control door lock receiver (RCDLR) does not receive a valid RF response after the transmitter is challenged, the RCDLR will not send a fuel enable message to the engine control module (ECM). If the RCDLR is unable to establish communication with the transmitter during an attempted engine start, the NO FOB DETECTED message will display on the driver information center (DIC).

When any one of the 4 allowable programmed key fobs are challenged by pressing the start button, they will passively send a RF signal to the RCDLR. The RCDLR will then send a serial data message to the engine control module (ECM) to enable engine starting.

Keyless Entry Antenna - Backup
The backup keyless entry antenna is located in the glove box area. It has a small pocket next to it where the transmitter can be inserted if the transmitter battery is dead, weak, or the RF signal is being interrupted.

The purpose of the backup keyless entry antenna is to send a low frequency RF challenge to a programmed transmitter within the interior of the vehicle when the start button is pressed. The backup keyless entry antenna is controlled by the remote control door lock receiver (RCDLR).

Body Control Module (BCM)
Important: The remote control door lock receiver (RCDLR) does not communicate on the GM LAN high speed bus. The RCDLR and the engine control module (ECM) use the BCM as a gateway in order to communicate.

The body control module is a multi-function module. The body control module (BCM) is used in the immobilizer system as a gateway for the RCDLR to send a fuel enable message to the ECM.

Remote Control Door Lock Receiver (RCDLR)
Important: The RCDLR does not communicate on the GM LAN high speed bus. The RCDLR and the engine control module (ECM) use the body control module (BCM) as a gateway in order to communicate.

The backup keyless entry antenna is controlled by the RCDLR. The RCDLR also controls three other low frequency antennas used for passive vehicle entry, but not for immobilizer operations. The RCDLR will send an AC voltage signal and provide ground to the backup keyless entry antenna when the ignition button is pressed. This will enable the backup keyless entry antenna to send out a low frequency broadcast challenge to a transmitter. The RCDLR also has an internal radio frequency (RF) antenna to receive the transmitters passively or actively sent responses. The RCDLR is responsible for sending the fuel enable message to the ECM if all the requirements are met.

Security Indicator
The security indicator appears on the instrument cluster. If the security indicator flashes or is illuminated continuously during vehicle operation, a malfunction exists within the immobilizer system. The security indicator is a dual purpose indicator. With the ignition OFF, the indicator it is controlled by the body control module (BCM) as a status indicator for the content theft deterrent system. With the ignition ON, it is controlled by the immobilizer system as a fault indicator.

Engine Control Module (ECM)
Important: The remote control door lock receiver (RCDLR) does not communicate on the GM LAN high speed bus. The RCDLR and the ECM use the body control module (BCM) as a gateway in order to communicate.

The ECM communicates with the BCM and the RCDLR over the serial data line. If the RCDLR receives a valid transmitter RF response, the RCDLR will send the fuel enable message to the ECM to enable the starting system. If the RCDLR does not receive a valid response from the transmitter, the RCDLR will send the fuel disable message, indicating to the ECM that vehicle starting should not be allowed. Additionally, if the fuel enable password received by the ECM does match the stored password, vehicle starting will be disabled.
© 2009 General Motors Corporation. All rights reserved.

[WorldClassRS]

xTooltipElement
Service Information
2010 Chevrolet Corvette | Corvette (VIN Y) Service Manual | Safety and Security | Remote Functions | Description and Operation | Document ID: 1456344
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Keyless Entry System Description and Operation
Keyless Entry System Description and Operation - Active
The keyless entry system is a vehicle entry device. Use the keyless entry system in conjunction with the door locks to unlock a vehicle. The keyless entry will unlock/unlatch the vehicle doors or open the rear compartment lid when a corresponding button on the key fob is pressed. This is accomplished by the key fob sending a radio frequency to the remote control door lock receiver (RCDLR). The signal is received by the RCDLR via an internal antenna located within the RCDLR. Japan export vehicles are equipped with an external antenna. The RCDLR interprets the signal and activates the requested function via a class 2 message over the serial data line. A low transmitter battery or radio frequency (RF) interference from aftermarket devices such as 2-way radios, power inverters, cellular phone chargers, computers, etc. may cause a system malfunction. High RF traffic areas, such as gas stations which use pay-at-the-pump RF transponders, may also cause interference that could lead to a malfunction.

Keyless entry allows you to operate the following components:

• The door locks

• The rear compartment lid release

• The illuminated entry lamps

The active keyless entry system has the following components:

• The #1-#4 keyless entry transmitters

• The remote control door lock receiver (RCDLR)

• External antenna (Japan export only)

Keyless Entry System Description and Operation - Passive
The passive keyless entry allows you to enter a locked vehicle without pressing any button on the key fob transmitter. You must only have the fob with you. This passive system is also part of the vehicle starting system. It allows you to start and run the vehicle having only the fob as your key. The passive entry and starting system use low frequency antennas in 4 different areas on the vehicle to determine the location of the key fob to the vehicle. When passively opening a locked door or a rear compartment lid, you must have a programed key fob with you in your pocket/purse/breifcase. As a customer presses an exterior door handle switch or exterior rear compartment lid release switch, the low frequency antenna sends out a challenge to the key fob. The key fob must be in a one meter range of the door or rear compartment lid that the customer is opening in order to receive the challenge. If the challenge from the low frequency antenna is met, the key fob will respond to the remote control door lock receiver (RCDLR) via a radio frequency signal allowing the door to be unlocked and opened. Starting the vehicle also works in the same manner. The key fob must be within the passenger compartment of the vehicle when the Start/ACC/OFF button is pressed. The low frequency antenna sends a challenge to the key fob and if the challenge is met, the fob will respond to the RCDLR. The RCDLR will then send out a fuel enable password to the engine control module (ECM). As long as all security requirements are met and the ECM receives the password over the serial data line, the engine will start and run. A low transmitter battery or radio frequency (RF) interference from aftermarket devices such as 2-way radios, power inverters, cellular phone chargers, computers, etc. may cause a system malfunction. High RF traffic areas, such as gas stations which use pay-at-the-pump RF transponders, may also cause interference that could lead to a malfunction.

The passive keyless entry has the following components:

• The transmitters, up to 4 total

• The RCDLR

• The keyless entry antenna - left, located in the lower B-pillar area at door height

• The keyless entry antenna - Right, located in the lower B-pillar area at door height

• The keyless entry antenna - rear, located in the rear compartment area near the rear compartment lid latch

• The keyless entry antenna - back up, located inside the passenger compartment inside the glove box area

Keyless Entry Transmitters
The keyless entry transmitters are used to passively or actively lock and unlock the vehicle. When any one of the 4 allowable programmed key fobs are challenged by a keyless entry antenna by depressing either of the exterior door open switches, the transmitters will passively send an RF signal to the remote control door lock receiver (RCDLR) via the door antennas. The RCDLR will then interpret this communication and either allow entry into the vehicle, or deny it.

Keyless Entry Antennas
The keyless entry antennas are used to transmit and receive RF communication with the keyless entry transmitters when accessing the vehicles doors or rear compartment.

The antennas are controlled by the remote control door lock receiver (RCDLR). When an exterior door handle switch or exterior rear compartment lid release switch is pressed, the respective antenna sends out a challenge to the transmitter, which begins the passive entry communications.

The keyless entry antenna backup is located in the glove box area. It has a small pocket next to it where the key fob can be inserted if the key fobs battery is dead, weak or the radio frequency (RF) signal is being jammed.

The purpose of the keyless entry antenna backup is to send a low frequency RF challenge to a programmed key fob, inside the interior of the vehicle, when the start button is pressed. The keyless entry antenna backup is controlled by the RCDLR.

Remote Control Door Lock Receiver (RCDLR)
Important: The remote control door lock receiver (RCDLR) is not on the GM LAN high speed bus, therefore the RCDLR and the engine control module (ECM) must use the body control module (BCM) as a gateway in order to communicate.

The RCDLR is a multi-function module located in the center of the dash panel. The keyless entry antennas are controlled by the RCDLR to allow passive vehicle entry, as well as vehicle starting and vehicle theft deterrent operations. The RCDLR will send an AC voltage signal and provide ground to the keyless entry antenna when an exterior door handle switch, exterior rear compartment lid release, or the Start/Acc/Off switch is depressed. This will enable the keyless entry antenna to send out a low frequency broadcast challenge to a key fob in range. The RCDLR also has an internal radio frequency (RF) antenna to receive the key fobs passively or actively sent signal.

Starting the Vehicle/ACC mode
To start a vehicle you must have a valid key fob present within the passenger compartment of the vehicle, the brake pedal depressed and the transmission in Park or Neutral. If there are no problems with key fob detection, the vehicle will be able to be started or put into accessory mode when the Start/ACC/OFF mode button is pressed. If a key fob is not detected or the radio frequencies are being interrupted, a message will display on the driver information center (DIC) stating NO FOB DETECTED. A NO FOB DETECTED message may be caused by a low transmitter battery or radio frequency (RF) interference from aftermarket devices such as 2-way radios, power inverters, cellular phone chargers, computers, etc. High RF traffic areas, such as gas stations which use pay-at-the-pump RF transponders, may also cause interference. A NO FOB DETECTED message caused by an aftermarket device or high RF traffic is considered normal and does not require the replacement of any components. Replacing components in these situations will typically not increase the performance of the system. Simply moving the fob to a different location inside the vehicle may allow key fob communication to continue. If moving the key fob within the vehicle does not correct the message, a pocket is located in the glove box for the key fob to slide into. The key fob must be inserted into the pocket bottom edge first with the buttons facing towards the passenger side of the vehicle. With the key fob inserted into the pocket correctly, a low frequency coupling will occur between the key fob and the antenna when the Start mode or ACC/OFF mode button is pressed. This procedure will put the vehicle in limp home mode and allow the vehicle to be operated.

Ignition ON Engine OFF mode
This mode is used to have all modules powered up and communicating on the serial data line. In order to achieve this mode the customer must have a valid key fob within the passenger compartment of the vehicle, the brake pedal depressed, and the transmission in Park or Neutral. Once that criteria is met, the customer must press and hold for 5 seconds the ACC/OFF portion of the Start/ACC/OFF mode button. The vehicle will power up with the engine OFF. A low transmitter battery or radio frequency (RF) interference from aftermarket devices such as 2-way radios, power inverters, cellular phone chargers, computers, etc. may cause a system malfunction. High RF traffic areas, such as gas stations which use pay-at-the-pump RF transponders, may also cause interference that could lead to a malfunction.

Turning OFF the Vehicle
When a vehicle is in a normal RUN mode, the key fob should already be present within the passenger compartment. To switch the vehicle to OFF mode, press the ACC/OFF portion of the Start/ACC/OFF mode button and the vehicle will power OFF. If a key fob is not detected or the radio frequencies are being interrupted, a message will display on the driver information center (DIC) stating NO FOB DETECTED. A NO FOB DETECTED message may be caused by a low transmitter battery or radio frequency (RF) interference from aftermarket devices such as 2-way radios, power inverters, cellular phone chargers, computers, etc. High RF traffic areas, such as gas stations which use pay-at-the-pump RF transponders, may also cause interference. For a vehicle to transition to the OFF mode, automatic transmissions must be placed in Park and manual transmissions must be placed in Reverse. If the transmission is not in Park (automatic transmissions) or Reverse (manual transmissions) when the OFF button is pressed, the engine will shut off, but the vehicle will remain the ACC mode. Should this occur, vehicles equipped with an automatic transmission will automatically switch to the OFF mode after approximately 10 minutes. Vehicles equipped with a manual transmission, however, will not transfer out of the ACC mode. Manual transmission vehicles will remain in the ACC mode which will cause a parasitic battery draw. Vehicles left in this ACC mode state are considered to still have the fob in the vehicle and may be started without a fob should the operator exit the vehicle.

While in normal RUN mode if the key fob is removed from the vehicle it will not stall; the vehicle will continue to run as normal. However, if the vehicle is attempted to be powered OFF with no key fob present, the driver information center (DIC) will display a message to the customer stating NO FOB, OFF or RUN? At this point the customer has a final opportunity to continue to run the vehicle. Once a running vehicle is powered OFF with out a key fob present, the vehicle will not be able to be restarted until a valid key fob is present. On a normal power OFF, if the customer is exiting the vehicle and the key fob is left in the passenger compartment, the horn will chirp three times alerting the customer the key fob has been left in the vehicle. This feature can be turned On/Off through DIC personalization.

Unlock Driver Door Only - Active
Momentarily press the key fob UNLOCK button in order to perform the following functions:

• Unlock only the driver door.

• Illuminate the interior lamps for approximately 40 seconds, or until the ignition is turned ON.

• Flash the exterior lights, if selected ON in personalization.

• Disarm the content theft deterrent (CTD) system, if equipped.

• Deactivate the CTD system when in the alarm mode.

Unlock All Doors - Second Operation - Active
Momentarily press the key fob UNLOCK button a second time, within 4 seconds of the first press, to perform the following functions:

• Unlock the remaining doors.

• Illuminate the interior lamps for approximately 40 seconds, or until the ignition is turned ON.

• Flash the exterior lights, if selected ON in personalization.

• Chirp the horn.

Unlock Driver Door Only - Passive
Approach the drivers door with a valid key fob to perform the following functions:

• Unlock only the driver door when the driver door handle pad is pressed.

• Disarm the content theft deterrent (CTD) system, if equipped.

• Deactivate the CTD system when in the alarm mode.

Unlock All Doors - Passive
Approach the drivers door with a valid key fob to perform the following functions:

• Unlock the driver and passenger door when the driver side door handle is pressed; this feature may be turned On/Off through personalization.

• Disarm the content theft deterrent (CTD) system, if equipped.

• Deactivate the CTD system when in the alarm mode.

or

Approach the passenger door with a valid key fob to perform the following functions:

• Unlock the passenger and driver door when the passenger side door handle is pressed.

• Disarm the content theft deterrent (CTD) system, if equipped.

• Deactivate the CTD system when in the alarm mode.

Lock All Doors - Active
Press the key fob LOCK button to perform the following functions:

• Lock all vehicle doors. Immediately turn off the interior lamps.

• Flash the exterior lights, if selected ON in personalization.

• Arm the content theft deterrent (CTD) system.

Lock All Doors - Passive
With passive locking enabled in the DIC personalization, exit the vehicle with the key fob to perform the following functions:

• Lock all vehicle doors, if selected On in personalization.

• Chirp horn, is selected ON in personalization.

• Arm the content theft deterrent (CTD) system.

Rear Compartment Lid Release - Active
If the vehicle transaxle is in PARK or NEUTRAL and the ignition is in the OFF position, a single press of the key fob rear compartment release button will open the rear compartment lid.

Rear Compartment Lid Release - Passive
Approach the rear of the vehicle with a valid key fob, push the rear compartment open pad the rear compartment lid will open.

Keyless Entry Personalization
The following items may be personalized through the DIC for Driver 1 or Driver 2:

• Flash at unlock, Yes/No

• Flash at lock, Yes/No

• Fob reminder, On/Off

• Passive door locking, Off/Silent/Horn

• Passive door unlock, Driver/Both

Key fobs programmed for Driver 1 and Driver 2 can be programmed to recall personalization features. When the vehicle is accessed with the 3rd or 4th programmed fob, OPTIONS NOT AVAILABLE is displayed on the DIC. With the 3rd or 4th programmed fobs, personalization settings can be changed only for the ignition cycle. None of the personalization settings selected or changed can be recalled with the 3rd or 4th programmed key fob. Accessing the vehicle with any key fobs not programmed for Driver 1 or Driver 2 causes the OPTIONS NOT AVAILABLE message to display on the DIC. For more information on programming instructions and personalization, refer to the Owners Manual.

Low Fob Battery Message
A LOW FOB BATTERY message may be seen on the DIC when the fob’s battery voltage has been lower than 2.6 volts for three consecutive ignition cycles (OFF to ACC or OFF to RUN). The RCDLR monitors the voltage of each fob independently; however, if two fobs are present when starting the vehicle, the voltage will be monitored only on the fob that starts the vehicle. For example, if Fob 1 enters from the driver door and Fob 2 enters from the passenger door, the RCDLR will monitor only Fob 1. To determine the fob being monitored, check which driver ID is present when the vehicle is started. The driver ID will correspond with the fob being monitored.

Fob battery voltage may also be observed using the scan tool. The scan tool displays the actual battery signal voltage, as well as the low voltage signal. These parameters may be used to determine which fob has caused the LOW FOB BATTERY message to be displayed.
© 2009 General Motors Corporation. All rights reserved.

[2SSRS@Gen5diy]

Thanks that is so good now will have to find how to make the BCM think the key is in.

[THUMPER20X]

Originally Posted by 2SSRS

I removed the battery in the fob and put it in the ignition and started the car, There was no problems i did 4 times.

Its possible there is a second nonreplaceable battery for the Passkey only. So that if you kill the battery using the keyless you can still start the car.

[2SSRS@Gen5diy]

This is from all the posts from "WorldClassRS"

When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coil surrounding the ignition lock cylinder. This exciter coil is part of the theft deterrent module. The energized transponder transmits a signal that contains its unique value, which is received by the BCM. The BCM then compares this value to a value stored in memory. The BCM also monitors various modules to determine that the stored security code matches.