gauges start jumping around and my stereo stops working?

Hi,

It sounds like the battery was failing or not being recharged. Is it fully charged? If so, turn the key to the run position. Allow it to remain in the on position for approx ten minutes.

If it is an issue with the anti-theft system, the light should turn off and allow the engine to start.

Try this and let me know what you find.

Joe

Security will not be an issue if the light is not flashing but a bad BCM can cause the not start issue and the gauges jumping around, if the engine is cranking over strong the battery is okay. I have also seen a bad alternator cause this issue as well due to throwing AC voltage.

This guide can help see if that is the problem once the engine is running:

https://www.2carpros.com/articles/how-to-check-a-car-alternator

I would run the codes to see if any are stored which will help us see what's going on.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Here is how to change out the BCM correctly. You can order a preprogrammed unit by searching eBay or Google. Check out the images (below). Please upload pictures or videos in your response to the problem so we can see what's going on.

I just replaced my battery a few weeks ago and the alternator is good. I ordered a new BCM from rockauto and it said it is plug n play no flash required but I'm worried it still will need to be programed. I'm going to the junk yard to pick up the three connectors cause the old ones are bad so when the new BCM gets here I will hook it up and do the relearn process with the key. Hopefully she starts up and it's actually plug n play like it says it is. I don't know.

If the BCM needs programming, you will know because the security light will flash when trying to start it. Please let us know what happens.

Does anyone know what the three connectors that go into the BCM are called? I can't find them online. I may just got to the junk yard and cut them off another grand am.

They are called "pigtail connectors" for the BCM, here is one with the BCM itself for $60.00:

https://www.ebay.com/itm/115896603255?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=115896603255&targetid=1645685074528&device=c&mktype=pla&googleloc=9031538&poi=&campaignid=20133407470&mkgroupid=147476396765&rlsatarget=pla-1645685074528&abcId=9312979&merchantid=101822193&gad_source=1&gclid=CjwKCAjwnv-vBhBdEiwABCYQA8aINUJ352AeU1R2-CkupkKy_hK1Jl_cqMw0rOSlIWq7NygUF09EfhoC66oQAvD_BwE

Let me know if this works, please.

I already ordered a brand new one and it says its plug and play no flash required so hopefully that's the case, but I got the three pigtail connectors today and noticed when I cut my old ones off that there are multiple wires with the same colors on each connector. I really need a pin out diagram of the BCM and connectors to help me figure out what goes where. I don't know how I'm going to figure out which pink or light blue wire goes where since there's double on each connector.

Also, when I had my other BCM connected it threw u1000 code class 2 serial and a theft deterrent code. Plus, one of the pins on the BCM broke off and is stuck inside the old connector, I'm guessing because it was so corroded.

This is the old middle connector with the pin still stuck inside it. I was going to try to pull it out and solder it back on the BCM but just decided to buy a new one. Guess I'll find out if Rockauto was truthful about the new one being plug n play unless when I plug my old BCM back up with new connectors and it works.

I put the new connectors on it, and everything comes back on like normal, but it won't start. Doesn't crank or anything. Security light not blinking, and this is my original BCM.

Here are the BCM wiring diagrams and a guide to help you check the wiring:

https://www.2carpros.com/articles/how-to-check-wiring

Check out the images (below). Please let us know what happens.

B2948, P1626, U1000, and C1298.
These codes are coming up on my car.

Could it be my ignition switch? There is a recall on it is think.

Maybe, I would turn the key on and check for power at these fuses, here is a guide to help:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

You should have power at all of them. Check out the images (below). Let us know how it goes.

Ok, I recently had some issues with my BCM connectors being corroded causing weird problems like radio not working dome lights not working, car would just act funny. So I just got some others from the junk yard and hooked them up and now everything comes on except it won't crank. The security light is just solid Not flashing so does it still need to do the relearn process?

Yep, here is how the relearn process is done:

BODY CONTROL MODULE (BCM) PROGRAMMING/RPO CONFIGURATION

1. The body control module BCM must be programmed with the proper RPO configurations. The BCM stores the information regarding the vehicle options and if the BCM is not properly configured with the correct RPO codes, the BCM will not control all of the features properly. Ensure that the following conditions exist in order to prepare for BCM programming:
- The battery is fully charged.
- The ignition switch is in the ON position.
- The data link connector (DLC) is accessible.
- All disconnected modules and devices are reconnected before programming.
2. To setup a new BCM, access the SPECIAL FUNCTIONS menu on the scan tool to program the BCM. Select NEW BCM SETUP and follow the instructions on the scan tool.
3. If the BCM fails to accept the program, perform the following steps:
- Inspect all BCM connections.
- Verify that the scan tool has the latest software version.

Passlock Learn Procedures

IMPORTANT: If any module or device listed is replaced, programming of the module must be done prior to performing the Passlock Learn procedure.

Perform the Learn Procedure if any of the following components have been replaced:
- The body control module, BCM
- The Passlock sensor
- The powertrain control module PCM

IMPORTANT: After programming, perform the following to avoid future misdiagnosis:

1. Turn the ignition OFF for 10 seconds.
2. Connect the scan tool to the data link connector.
3. Turn the ignition ON with the engine OFF.
4. Use the scan tool in order to retrieve history DTCs from all modules.
5. Clear all history DTCs.

Please let us know what happens.

I didn't change the BCM just the connectors, my ignition has been acting up too. It has been sticking in the start position i need to check the ignition switch too. I don't need to reprogram it if I'm using the same BCM right? Just the keys relearn?

That is correct.

I need the wire pin out of the BCM. I have the new bcm hooked up but my security light is on and i have codes coming up. Airbags and theft deterrent.

They are not giving the BCM pinouts on Alldata. You are going to have to use the BCM wiring diagrams above.

My scanner won't do some of the relearns. Its an Innova 5610.

Can you clear the code and then turn the key on without starting the engine to see if any come up?

I'll see if any come back up.

Can I unplug a connector from BCM to check with multimeter?

Yep, use the meter to check the continuity.

I have a security system sensor circuit high code too and a relearn, but it starts up and drives but the 10min relearn doesn't get the light off. My reverse lights are not working either. Well, the bottom ones are but the ones by my taillights are not. The truck release on the driver's side door too. Maybe I didn't get a good enough connection when I crimped the new connectors on. I'll check that one connector and see.

Sorry for asking so many questions, I've been able to drive my car, but the security light stays on, and my reverse lights don't work. My radio and dash lights sometimes don't work. I got a new ignition lock cylinder because the old one is sticking when I start it up, so it'll die if I don't bring the key back to the run position. Could that be causing my lights and radio not working sometimes? It's just confusing me and I'm not the greatest when it comes to electrical stuff.