14 Camaro SS donor to 1970 Chevelle alarm/lock issues - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

pcguy2u · 07-21-2022, 12:51 PM

Need to start a discussion about pull-up resistors and when momentary actuators (vs solid contact signals) are required...

Here's the circuit I'm having trouble with:

First question is why there is no door lock (circuit 3270) status on the passenger (right) side?

The alarm triggers when the hood or the trunk open, but not when either of the doors open.

Hopefully someone understands this better than I do.

Nick

gtstorey · 07-21-2022, 01:19 PM

The Camaros with power locks have a single switch in the middle of the dash for lock and unlock. I think the switches that you marked on the driver door are (maybe) the driver door key lock/unlock and the manual lock by pushing down on the door lock knob. The other way to unlock is pull the door handles, but I'm not sure that is shown.

https://camarosofmichigan.com/2014/2...manual-min.pdf

gtstorey · 07-21-2022, 01:51 PM

After a little more thought and study,
3270 is the door key lock/unlock.
5911 is unlock signal from the driver door handle
294 is lock signal from the lock knob on either door
295 is unlock signal from the passenger door handle
745/746 is lock/unlock driven from the window motor (actually has a logic/module function) as instructed by the BCM.
780/781 is the center of dash lock/unlock button controlled by logic in the radio/hvac module.
What I'm not real sure on is which one of the switches in the door latch assemblies are actually a mechanical lock (if any) and what is just a signal switch.

pcguy2u · 07-22-2022, 09:57 AM

The 745 and 746 circuits seem to be the most logical culprits, especially since they both reference data communications with the BCM. Not sure how to deal with that, but I have still have the OEM Camaro window motor driver connected without the motor itself.

Here is a pinout of the plug to the door latches:

gtstorey · 07-22-2022, 10:04 AM

What are you trying to accomplish? Getting the alarm to work when the doors are opened?

pcguy2u · 07-22-2022, 10:22 AM

That's the goal; not sure what else may be encountered after I get that to work properly...

The problem that underlies all of this is that there is no explanation (semantics) for what happens in either the latch or the BCM. Have reached out to the local dealership Service Manager who passed on my request for that info to a friend/GM engineer --- crickets... :o(

Testing of the latch on the bench has proven futile because I no longer have a working analog multimeter. Digital meters have a lag time so a transient/momentary signal/short are not evident. I have ordered an analog meter which should be here soon.

gtstorey · 07-22-2022, 10:22 AM

What is the "T" symbol beside the BCM X6, Pins 1, 2 & 4 represent?

Do you have the door latch assembly installed or one you can play with?

gtstorey · 07-22-2022, 10:24 AM

What do you have in place to tell the BCM that the doors are locked?

pcguy2u · 07-22-2022, 10:31 AM

The legend shows that to be "I/O Bidirectional Switch (+/-)

The only latch I have that works, or at least I think it works, is sitting in a plastic bag in the bottom of the driver's door. I will be putting that on the bench when the analog meter arrives. As a result of previous attempts to get this right I have wired it in parallel and I can't be sure of how that is working, or not...

gtstorey · 07-22-2022, 10:46 AM

can you not check the function of the momentary switch with a powered test light or a bulb.

At this point I'm speculating;
The momentary switch will just momentarily ground and the module will be tracking the status and will use that ground signal to know to swap states. So if circuit 745 is grounded it will tell the window module that it has changed state and will relay that info to the BCM. I don't know if the actual status of the door (open or closed) is stored in the window module or the BCM. This is based upon the switch actually being momentary. It wouldn't surprise me if it's not really momentary and actually is just grounded in one state and open in the other (basically the way door ajar switches used to work).

pcguy2u · 07-22-2022, 11:03 AM

Quote:

Originally Posted by gtstorey

can you not check the function of the momentary switch with a powered test light or a bulb.

At this point I'm speculating;
The momentary switch will just momentarily ground and the module will be tracking the status and will use that ground signal to know to swap states. So if circuit 745 is grounded it will tell the window module that it has changed state and will relay that info to the BCM. I don't know if the actual status of the door (open or closed) is stored in the window module or the BCM. This is based upon the switch actually being momentary. It wouldn't surprise me if it's not really momentary and actually is just grounded in one state and open in the other (basically the way door ajar switches used to work).

The light bulb test should also work, but the only working switch I have is in a plastic bag at the bottom of the door and this is all about planning for it's removal/modification. I also have found other needs for an analog meter so I ordered one earlier this week.

gtstorey · 07-22-2022, 12:08 PM

GM maybe (probably?) just using the "momentary" to indicate non-latching.

I'm don't see how you are going to get this to work without incorporating the switches as designed by GM. I would expect the BCM to need feedback from most if not all of those switches to know what to do. I would think even the 5911, 294, 295 would have to be replicated since I think they act as switches in addition to actuators, similar to the way the cheap aftermarket magnetic door lock actuators work to tell the controller that the doors have been locked/unlocked with the knobs. But this is beyond the stuff that I have done with rewiring switches to emulate oem on my kit car. We eliminated all of the door stuff and don't know that it had this stuff built in anyway (2009 Chevy Cobalt donor).

pcguy2u · 07-22-2022, 12:35 PM

Quote:

Originally Posted by gtstorey

What do you have in place to tell the BCM that the doors are locked?

The OEM Chevelle latches were modified to support a 12VDC solenoid that both locks and unlocks as it is supposed to and also has a set of contacts that signals the state of the locks. Mind you the contacts are old school and not momentary.

gtstorey · 07-22-2022, 12:45 PM

Again, you need to check to see of the "momentary" just means non-latching if you haven't already. It seems to me the key lock switch especially would just mean non-latching, since it would have to work if you hold the key in the lock/unlock position.

07-21-2022, 12:51 PM	#1
pcguy2u Drives: 2009 Corvette ZR1 Join Date: Aug 2012 Location: On the coast North of SFBay Posts: 297	14 Camaro SS donor to 1970 Chevelle alarm/lock issues Need to start a discussion about pull-up resistors and when momentary actuators (vs solid contact signals) are required... Here's the circuit I'm having trouble with: First question is why there is no door lock (circuit 3270) status on the passenger (right) side? The alarm triggers when the hood or the trunk open, but not when either of the doors open. Hopefully someone understands this better than I do. Nick __________________ Here's a link to my 70 Chevelle build thread: https://www.chevelles.com/forums/12-...aro-donor.html

07-22-2022, 09:57 AM	#4
pcguy2u Drives: 2009 Corvette ZR1 Join Date: Aug 2012 Location: On the coast North of SFBay Posts: 297	The 745 and 746 circuits seem to be the most logical culprits, especially since they both reference data communications with the BCM. Not sure how to deal with that, but I have still have the OEM Camaro window motor driver connected without the motor itself. Here is a pinout of the plug to the door latches: Attached Images __________________ Here's a link to my 70 Chevelle build thread: https://www.chevelles.com/forums/12-...aro-donor.html

07-22-2022, 10:22 AM	#6
pcguy2u Drives: 2009 Corvette ZR1 Join Date: Aug 2012 Location: On the coast North of SFBay Posts: 297	That's the goal; not sure what else may be encountered after I get that to work properly... The problem that underlies all of this is that there is no explanation (semantics) for what happens in either the latch or the BCM. Have reached out to the local dealership Service Manager who passed on my request for that info to a friend/GM engineer --- crickets... :o( Testing of the latch on the bench has proven futile because I no longer have a working analog multimeter. Digital meters have a lag time so a transient/momentary signal/short are not evident. I have ordered an analog meter which should be here soon. __________________ Here's a link to my 70 Chevelle build thread: https://www.chevelles.com/forums/12-...aro-donor.html

07-22-2022, 10:31 AM	#9
pcguy2u Drives: 2009 Corvette ZR1 Join Date: Aug 2012 Location: On the coast North of SFBay Posts: 297	The legend shows that to be "I/O Bidirectional Switch (+/-) The only latch I have that works, or at least I think it works, is sitting in a plastic bag in the bottom of the driver's door. I will be putting that on the bench when the analog meter arrives. As a result of previous attempts to get this right I have wired it in parallel and I can't be sure of how that is working, or not... __________________ Here's a link to my 70 Chevelle build thread: https://www.chevelles.com/forums/12-...aro-donor.html

07-21-2022, 01:19 PM	#2
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,149	The Camaros with power locks have a single switch in the middle of the dash for lock and unlock. I think the switches that you marked on the driver door are (maybe) the driver door key lock/unlock and the manual lock by pushing down on the door lock knob. The other way to unlock is pull the door handles, but I'm not sure that is shown. https://camarosofmichigan.com/2014/2...manual-min.pdf

07-21-2022, 01:51 PM	#3
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,149	After a little more thought and study, 3270 is the door key lock/unlock. 5911 is unlock signal from the driver door handle 294 is lock signal from the lock knob on either door 295 is unlock signal from the passenger door handle 745/746 is lock/unlock driven from the window motor (actually has a logic/module function) as instructed by the BCM. 780/781 is the center of dash lock/unlock button controlled by logic in the radio/hvac module. What I'm not real sure on is which one of the switches in the door latch assemblies are actually a mechanical lock (if any) and what is just a signal switch.

07-22-2022, 10:04 AM	#5
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,149	What are you trying to accomplish? Getting the alarm to work when the doors are opened?

07-22-2022, 10:24 AM	#8
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,149	What do you have in place to tell the BCM that the doors are locked?

07-22-2022, 10:46 AM	#10
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,149	can you not check the function of the momentary switch with a powered test light or a bulb. At this point I'm speculating; The momentary switch will just momentarily ground and the module will be tracking the status and will use that ground signal to know to swap states. So if circuit 745 is grounded it will tell the window module that it has changed state and will relay that info to the BCM. I don't know if the actual status of the door (open or closed) is stored in the window module or the BCM. This is based upon the switch actually being momentary. It wouldn't surprise me if it's not really momentary and actually is just grounded in one state and open in the other (basically the way door ajar switches used to work).

07-22-2022, 12:08 PM	#12
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,149	GM maybe (probably?) just using the "momentary" to indicate non-latching. I'm don't see how you are going to get this to work without incorporating the switches as designed by GM. I would expect the BCM to need feedback from most if not all of those switches to know what to do. I would think even the 5911, 294, 295 would have to be replicated since I think they act as switches in addition to actuators, similar to the way the cheap aftermarket magnetic door lock actuators work to tell the controller that the doors have been locked/unlocked with the knobs. But this is beyond the stuff that I have done with rewiring switches to emulate oem on my kit car. We eliminated all of the door stuff and don't know that it had this stuff built in anyway (2009 Chevy Cobalt donor).

07-22-2022, 12:45 PM	#14
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,149	Again, you need to check to see of the "momentary" just means non-latching if you haven't already. It seems to me the key lock switch especially would just mean non-latching, since it would have to work if you hold the key in the lock/unlock position.