Intermittent starts, transmission not shifting?

2004 CHEVROLET MALIBU

143,000 MILES • 3.5L • V6 • 2WD • AUTOMATIC

RUDYGIA

MEMBER
1 POST

Sometimes the car will not start I get no power at ignition. Horn, cigarette lighter, and headlights will work. No dash lights no power door locks or windows, This has happened to me a few times and eventually the car will start, maybe days later. When the car does run, I also have trouble with the car shifting into 3rd gear. I was able to pull up a code on that which indicated shifter solenoid in transmission. I do not believe problems are related. Prior to this I had used the car for 3 months with no problems even after it had been sitting for about a year without use.

Jun 9, 2023 at 4:06 AM

STRAILER

✓Experienced Mechanic
55,249 POSTS

Yep, this happens when the BCM goes out, but to be sure we could do a CAN scan, you can get a CAN scanner (Controller Area Network) which will work on most cars from Amazon.

Here is a guide to help:

https://youtu.be/u-4syLc-ifQ

Here is how to change the BCM out and the location in the images below and a guide to help walk you through the repair. You can get a preprogrammed unit by searching Google or Ebay.

https://www.2carpros.com/articles/how-to-replace-a-bcm-body-control-module

Check out the images (below). Please let us know if you need anything else to get the problem fixed.

Images (Click to enlarge)

Professional Diagram for 2CarPros Members
Click here to log in and view diagram.

Jun 10, 2023 at 3:29 AM

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