Carlos R. Arias

Very interesting information and I think that is the problem that I have with my car head lights, radio, left side power window and some warning lights on at the dash board cluster indicating certain problems like water coolant empty, etc,,, and there is not such problem really. I'm also having problems with the transmission slippery which who knows could belong to this same problem.
My problem is that I can not see the control body module photo that you are referring to with the relays shown.
Could you please send me and e-mail with such photo to "aritran@prw.net".
Appreciated

skat4160

It would not have anything to do with your coolant light being on. I have replaced the sensor for that about 12 times in 20 years. It just seems to be an issue with the sensors. It also would not have anything to do with your transmission either. Totally separate problem. I don't know if it affects your headlights since I never had that problem. Just the radio and windows were effected in my 99 Z28. I did not post the pic of the Body Control Module removal and soldering but if you read all the links to BCM Problems you should be able to find it. Also Shoebox has videos on it I Think? White Bird knows a lot about it so look for his posts on here as well. I was going to replace mine last year since I don't know how to solder but alas GM in all their wisdom decided to Discontinue the part for my Z28 but they were still offering the module for Non remote entry which mine is not at GMParts.com if you want to go that route. Post on here and someone will lead you to what you need that knows more than I do. Good Luck

skat4160

That's what turned my Security Light on and it has never turned off. I used another Original key to start my car and let it warm up when it was 16 degrees out and I manually locked the door by sliding the lock then I used the Original door key to open the door and my Security light has been on steady ever since and I have had the battery replaced at Advance Auto and they plugged something into where you check for codes. They said to retain all my radio settings. But the Security light has been on going on 7 years now. What's that all about??

WhiteBird00

iTrader: (4)

As skat4160 has mentioned, the BCM fix described in this thread has nothing to do with your coolant light or transmission. Neither does it have anything to do with your headlights or any warning lights on the dash (the BCM does control a couple of the warning lights but this fix is not related). The only thing this fix does is repair a bad solder joint that affects the Retained Accessory Power (RAP) circuit which powers the radio and the windows for a period of time after the ignition is shut off or until a door is opened. If your radio is cutting out intermittently and your windows (both of them) stop working at the same time then this fix is for you. Otherwise, there is some other cause for your issues.

The BCM controls power door locks, keyless entry, retained accessory power (for radio and windows), courtesy lamps, vehicle anti-theft system (VATS), hatch release, optional alarm system, and various warning lights like seat belts, security, and door ajar.

If you read the whole thread, you will find that photos are included in later posts after the original poster left the forum in a snit and deleted all his photos. Look particularly at posts 185 through 189.

WhiteBird00

iTrader: (4)

The SECURITY light on the dash is controlled by the BCM to show problems with the VATS system. If it is on solid then VATS has detected a key resistor pellet in the ignition but with the wrong resistance value. If the light is flashing then VATS is unable to see a resistance value at all (key with no pellet or an open in the circuit).

If either condition occurs while starting the car then VATS will disable the starter relay and turn off the fuel enable signal to the PCM ensuring that the car won't start. But if the condition occurs while the car is already running then VATS will set a fault, illuminate the light, but still allow the car to start on the assumption that it's a circuit problem rather than the car being stolen. This would be what happened in your case. Be careful... this condition can go on for years without any issues other than the annoying light on the dash but there have been cases where the BCM appears to "reset" (usually after changing the battery) and then "discovers" the fault during the next starting cycle and prevents the car from starting. I would plan on doing a VATS bypass sooner rather than later just for the piece of mind that you won't be left stranded someplace.

GoatsZ28

Somy windows have not worked since i have had the car. (2 months) We just started trying to get them to work. I had the car on and when I push the window button on either side the radio dies and window does nothing on both sides of the car. We have pulled the breakers and replaced with a 30a fusee and no luck. radio works fine just dont try to get the windows to roll down and the door locks work as well.

Could the bcm be the issue?

WhiteBird00

iTrader: (4)

As described in your other thread on the subject, the chances of this being a BCM problem are next to nil. Especially with the new information that the windows have never worked since you got the car... I can almost guarantee that this is not a BCM issue.

Story to be continued in the original thread... https://ls1tech.com/forums/wiring-st...dio-issue.html

cancam99ss

iTrader: (8)

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