BCM Troubles?
10-04-2015, 01:09 AM
#1
BCM Troubles?
Recently had my car die in the staging lanes and refuse I restart. The starter wouldn't turn over and after several tries it would then kill the fuel pump and die. I loaded the car on the trailer, hauled it home and it fired up when home. Drive it around the block a few times and it died again and wouldn't restart. Figured the VATS was the problem. Got the correct ohms on the key and had a new one cut. Went to he track and car preformed perfectly. Went to the track again tonight and the car died and refused to restart in the lanes. Checked all BCM fuses/ all sat. Let it sit 15 min and it fired and ran long enough for me to get to the pits. First call to the lanes and it won't start again. Load it up to take it home 30 min later and just for fun decide to see if it will start. Fires right up 5 times in a row. Should I go through the trouble of fully replacing my BCM or is there a chance I am overlooking something? Maybe battery is getting weak and causing problems? Please help. 2 out of 3 trips breakin down at the track is getting frustrating.
10-04-2015, 11:51 AM
#2
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
YEP!!!
Been there,,,, done that!!
IF,,,,, that fails,, yiu can also try this:
Take the car OUT OF GEAR,, chock the wheels!!
In the passengers foot well, there is a relay on the fire wall (above and forward of the BCM. It has FOUR WIRES (RED, PURPLE, yellow and yellow/black stripe.
IF,, the car is having a BCM Security issue, find the YELLOW/BLACK stripe wire on that relay and GROUND IT to chassis ground. That will BY-PASS the BCM starter disable part of the security protocol. Once that wire is grounded, try to start the engine. If it cranks and runs, you have a BCM Security issue.
You can also use a jumper wire and jump the relay RED to PURPLE wire.
NOTE & WARNING!!!!!!!
When you jump those two wires, the STARTER WILL CRANK the engine! If its in gear, the car will MOVE!!!!! If the key is in RUN, the engine will start and leave the building!!!!
If you jump the purple and red wires and nothing happens, you have a defective solenoid, connection or starter issue.
Another simple check is to examine the wires at the starter solenoid. They MUST be clean, tight and not burnt up!!
Bill
Been there,,,, done that!!IF,,,,, that fails,, yiu can also try this:
Take the car OUT OF GEAR,, chock the wheels!!
In the passengers foot well, there is a relay on the fire wall (above and forward of the BCM. It has FOUR WIRES (RED, PURPLE, yellow and yellow/black stripe.
IF,, the car is having a BCM Security issue, find the YELLOW/BLACK stripe wire on that relay and GROUND IT to chassis ground. That will BY-PASS the BCM starter disable part of the security protocol. Once that wire is grounded, try to start the engine. If it cranks and runs, you have a BCM Security issue.
You can also use a jumper wire and jump the relay RED to PURPLE wire.
NOTE & WARNING!!!!!!!
When you jump those two wires, the STARTER WILL CRANK the engine! If its in gear, the car will MOVE!!!!! If the key is in RUN, the engine will start and leave the building!!!!
If you jump the purple and red wires and nothing happens, you have a defective solenoid, connection or starter issue.
Another simple check is to examine the wires at the starter solenoid. They MUST be clean, tight and not burnt up!!
Bill