2003 Impala New BCM Will Not Program
wwj745
05-23-2012, 01:55 PM
I have a 2003 Impala. My car has these problems, ABS light on most of the time, check engine light on most of the time. Sometimes the fob will not unlock the doors and when I get in and turn the key there is nothing. I have to turn the key several times to start before it will actually start. Took it to the shop and it was diagnosed as a bad BCM.
The new BCM will not program. They have had it to the dealership, checked every electrical connection, every sensor. every buss and even tried to program the ECM and the new BCM at the same time. Yet the new BCM will not program. My mechanic is now contacting GM directly. Any ideas???
The new BCM will not program. They have had it to the dealership, checked every electrical connection, every sensor. every buss and even tried to program the ECM and the new BCM at the same time. Yet the new BCM will not program. My mechanic is now contacting GM directly. Any ideas???
gmtech1
05-23-2012, 04:52 PM
The programing for the BCM, and its more of a set-up procedure than programing, is done with a tech2 scanner. Is there power and ground at the BCM? If not, it will not program. Not sure how they could have tried to program the PCM at the same time since they use different procedures. Check the left side I/P fues box for any blown fuses.
wwj745
05-23-2012, 05:33 PM
The programing for the BCM, and its more of a set-up procedure than programing, is done with a tech2 scanner. Is there power and ground at the BCM? If not, it will not program. Not sure how they could have tried to program the PCM at the same time since they use different procedures. Check the left side I/P fues box for any blown fuses.
Correct, it is a programming issue. That is also the problem. The new BCM will not program.
My mechanic has the correct scanner. There is power to the BCM and it is grounded.
What they did was reprogram the ECM fresh and then tried to put the BCM program in thinking there may be somthing in the ECM program preventing the BCM from programming.
No blowen fuses.
Correct, it is a programming issue. That is also the problem. The new BCM will not program.
My mechanic has the correct scanner. There is power to the BCM and it is grounded.
What they did was reprogram the ECM fresh and then tried to put the BCM program in thinking there may be somthing in the ECM program preventing the BCM from programming.
No blowen fuses.
Tech II
05-23-2012, 07:32 PM
Took it to the shop and it was diagnosed as a bad BCM.
The new BCM will not program. They have had it to the dealership, checked every electrical connection, every sensor. every buss and even tried to program the ECM and the new BCM at the same time. Yet the new BCM will not program. My mechanic is now contacting GM directly. Any ideas???
So a "shop" tried to program a BCM......most shops are not capable of doing this.....if they tried to program the BCM, and failed, they could have "locked" the BCM, and it can no longer be programmed....like GMTech1 said, in some cases, you more or less set up a BCM.....in some cases, it's a little more involved....in some cases the Theft Deterrant system has to be programmed into the BCM, or the vehicle won't start.....that takes GM equiptment......I wasn't there, but if during the setup, power was lost to the vehicle(one reason why when programming, a special GM charger(that won't be affected by AC fluctuations) has to be used), then you can lose the BCM.....I'm sure the GM shop tried to straighten this out as a "favor", but they are not going to really dive into this situation to fix someone else's possible mistake.....
The new BCM will not program. They have had it to the dealership, checked every electrical connection, every sensor. every buss and even tried to program the ECM and the new BCM at the same time. Yet the new BCM will not program. My mechanic is now contacting GM directly. Any ideas???
So a "shop" tried to program a BCM......most shops are not capable of doing this.....if they tried to program the BCM, and failed, they could have "locked" the BCM, and it can no longer be programmed....like GMTech1 said, in some cases, you more or less set up a BCM.....in some cases, it's a little more involved....in some cases the Theft Deterrant system has to be programmed into the BCM, or the vehicle won't start.....that takes GM equiptment......I wasn't there, but if during the setup, power was lost to the vehicle(one reason why when programming, a special GM charger(that won't be affected by AC fluctuations) has to be used), then you can lose the BCM.....I'm sure the GM shop tried to straighten this out as a "favor", but they are not going to really dive into this situation to fix someone else's possible mistake.....
wwj745
05-24-2012, 08:13 AM
Took it to the shop and it was diagnosed as a bad BCM.
The new BCM will not program. They have had it to the dealership, checked every electrical connection, every sensor. every buss and even tried to program the ECM and the new BCM at the same time. Yet the new BCM will not program. My mechanic is now contacting GM directly. Any ideas???
So a "shop" tried to program a BCM......most shops are not capable of doing this.....if they tried to program the BCM, and failed, they could have "locked" the BCM, and it can no longer be programmed....like GMTech1 said, in some cases, you more or less set up a BCM.....in some cases, it's a little more involved....in some cases the Theft Deterrant system has to be programmed into the BCM, or the vehicle won't start.....that takes GM equiptment......I wasn't there, but if during the setup, power was lost to the vehicle(one reason why when programming, a special GM charger(that won't be affected by AC fluctuations) has to be used), then you can lose the BCM.....I'm sure the GM shop tried to straighten this out as a "favor", but they are not going to really dive into this situation to fix someone else's possible mistake.....
As I stated they have had it to the dealership also. My mechanic has done these before. He knows how to do it.
The new BCM will not program. They have had it to the dealership, checked every electrical connection, every sensor. every buss and even tried to program the ECM and the new BCM at the same time. Yet the new BCM will not program. My mechanic is now contacting GM directly. Any ideas???
So a "shop" tried to program a BCM......most shops are not capable of doing this.....if they tried to program the BCM, and failed, they could have "locked" the BCM, and it can no longer be programmed....like GMTech1 said, in some cases, you more or less set up a BCM.....in some cases, it's a little more involved....in some cases the Theft Deterrant system has to be programmed into the BCM, or the vehicle won't start.....that takes GM equiptment......I wasn't there, but if during the setup, power was lost to the vehicle(one reason why when programming, a special GM charger(that won't be affected by AC fluctuations) has to be used), then you can lose the BCM.....I'm sure the GM shop tried to straighten this out as a "favor", but they are not going to really dive into this situation to fix someone else's possible mistake.....
As I stated they have had it to the dealership also. My mechanic has done these before. He knows how to do it.
wwj745
10-27-2012, 01:23 PM
Well 5 months later and STILL no resolution. Going back and forth between the dealer and the factory rep. I am about ready to set fire to it!
wwj745
10-27-2012, 01:33 PM
I was incorrect in my earlier post. I thought he had tried to program the ECM. He had not. When he tried. it would not take updates or a new program either. Tried a new ECM. Same thing. So neither the BCM or ECM will accept updating/programing.
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