No Start -- Need Help!

[Jarhead1]

Originally Posted by gtstorey

One bad module will not cause the others to not communicate as long as it’s not the “master”, usually the bcm, that wakes them up. I’ve removed half the modules in my kit car and the remaining still communicate fine. When I replaced the eps that had the resistor to one that didn’t the communication got spotty so I had to add an external resistor to make the data communication work consistently.

Went through the exact same issue this month. Let me know if you ended up putting a ECM in it? After seeing the same story its not going to be BCM module. Getting them to read your old ECM to Match your BCM is still possible.

Best Wishes

C.J

[csymes15]

Originally Posted by Jarhead1

Went through the exact same issue this month. Let me know if you ended up putting a ECM in it? After seeing the same story its not going to be BCM module. Getting them to read your old ECM to Match your BCM is still possible.

Best Wishes

C.J

Replacing my BCM fixed 90% of the issues I was having (including the no start), but did not fully fix the communication issues
and had a friend program the BCM to match all the data off the old one so I didn't have to bring it to a dealer

Previously we had 0 communication between any modules; now we have intermittent communication

initial diag was that one of the modules was malfunctioning and causing the comm signal to get intercepted/grounded. By jumping/bypassing steering angle sensor we were able to get comm back up. so a new sensor was ordered.
Then comms went away again

While waiting for new ECM to come in, a new set of com lines was run from the connection on the firewall to the BCM and that renewed all communications.

So basically, a massive shit storm of things happened to go wrong all at once.

For anyone who is having a similar issue: check wiring harness, but if there is no clear issue with it then BCM is most likely the issue. Seems like these BCMs just shit the bed occasionally.

[Jarhead1]

Originally Posted by csymes15

Replacing my BCM fixed 90% of the issues I was having (including the no start), but did not fully fix the communication issues
and had a friend program the BCM to match all the data off the old one so I didn't have to bring it to a dealer

Previously we had 0 communication between any modules; now we have intermittent communication

initial diag was that one of the modules was malfunctioning and causing the comm signal to get intercepted/grounded. By jumping/bypassing steering angle sensor we were able to get comm back up. so a new sensor was ordered.
Then comms went away again

While waiting for new ECM to come in, a new set of com lines was run from the connection on the firewall to the BCM and that renewed all communications.

So basically, a massive shit storm of things happened to go wrong all at once.

For anyone who is having a similar issue: check wiring harness, but if there is no clear issue with it then BCM is most likely the issue. Seems like these BCMs just shit the bed occasionally.

Even though I received a rude reply from another so called expert claiming I needed to buy the books so I did. Not from some cd seller connected to this site I paid $275 for all three. I learned the following Yes the resistor has to match and if the BCM is Bad it should not start that's False. The Bcm stores a great deal more than I thought. But it stores only one Key so when reprogramming keep that in mind, My old ecm smelled like burnt dog Hair and would not communicate anymore with any meter! So I had to no choice to replace it. It's not the bcm! It's not the communications port. My old BCM values were restored once I hooked up the new ecm and recoded the keys anyway. Using the master as Key one and the car started up. Odds of your old ecm picking up data from the original bcm is slim . My suggestion would be restore the old bcm if possible.Otherwise you will never reach it without the key from any replacement bcm. No matter what, use the original key on the original bcm. BCM Programing on new bcm is strictly by dealer otherwise it will shut down all communications as you experience. Get the new ecm as soon as possible and start with the original BCM and let me know how you make out. I bet the car remembers more than you think. Hell mine remembered my wifi for my cell phone.

[csymes15]

Originally Posted by Jarhead1

Even though I received a rude reply from another so called expert claiming I needed to buy the books so I did. Not from some cd seller connected to this site I paid $275 for all three. I learned the following Yes the resistor has to match and if the BCM is Bad it should not start that's False. The Bcm stores a great deal more than I thought. But it stores only one Key so when reprogramming keep that in mind, My old ecm smelled like burnt dog Hair and would not communicate anymore with any meter! So I had to no choice to replace it. It's not the bcm! It's not the communications port. My old BCM values were restored once I hooked up the new ecm and recoded the keys anyway. Using the master as Key one and the car started up. Odds of your old ecm picking up data from the original bcm is slim . My suggestion would be restore the old bcm if possible.Otherwise you will never reach it without the key from any replacement bcm. No matter what, use the original key on the original bcm. BCM Programing on new bcm is strictly by dealer otherwise it will shut down all communications as you experience. Get the new ecm as soon as possible and start with the original BCM and let me know how you make out. I bet the car remembers more than you think. Hell mine remembered my wifi for my cell phone.

Not 100% sure exactly what you are talking about,
But programming is not as issue for me. My new BCM was properly programmed and functions exactly the same as the old one. For most people they will not have access to programming unless you go through a dealership.

A bad BCM 100% can keep the car from starting.

My car is running with new BCM
and the new BCM did restore communications
I just also happened to have an additional problems on top of the BCM.

The ECM was not replaced and is functioning properly now that everything else is corrected.

[Jarhead1]

Originally Posted by csymes15

Not 100% sure exactly what you are talking about,
But programming is not as issue for me. My new BCM was properly programmed and functions exactly the same as the old one. For most people they will not have access to programming unless you go through a dealership.

A bad BCM 100% can keep the car from starting.

My car is running with new BCM
and the new BCM did restore communications
I just also happened to have an additional problems on top of the BCM.

The ECM was not replaced and is functioning properly now that everything else is corrected.

You will Be You will Be Why ask for opinions when yours is the only one that counts Moderator

[Ltrevino206]

Man I’m having it been having the same issue. I’m gonna check grounds to ecm or my car has been popping up some certain communication code and I’m about to try to figure it out