Which pin needs power on stock harness to bypass security (Vats off in pcm already)
09-21-2009, 02:31 PM
#1
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Which pin needs power on stock harness to bypass security (Vats off in pcm already) I use a few different standalone wiring harness suppliers for my in house conversions etc... but this one is a stock fbody harness
But im having a bit of a problem that I getting to be a pain to figure out. My wifes 00 SS is stock 00 fbody 6-spd wiring harness etc.. one of my employees borrowed the BCM out of my car and the other car they tried it in fried the body control module (BCM) and I replaced it with another from a 00 Fbody I had laying around.
I dont have the ignition key from the new BCM so i cannot check and see what the OHMS on the pellet security key is so i can just wire in some resistors to bypass it. I did bypass the starter so it will crank no matter what, security cant shut off the starter. VATS is shut off in the PCM as well.
Now the car will occasionally not start and security light will come on. It happens probably once out of 10 times you start the car. It wasnt a big deal for the last month or so because if it didnt start, you just turn key off and back on and it would start right up. But this weekend it just cranked and cranked, couldnt get it to start. Let it sit for an hour, wouldnt start etc. Not till today did it finally start up (first try today).
When it doesnt start, its basically not giving power to the engine wiring harness because it gets no spark. Until the security thing goes away.
So I want to figure out what wire in the PCM pins or where I need to apply keyed power in the engine/body harness to make sure the key cannot disable power to the engine harness.
What wire would I give keyed power to, to ensure the harness is always powered. The easy solution would be buy a new BCM from GM and it will program itself to the key and I doubt I'd have another problem with it, but they are way overpriced so figured I could go around the problem easily
But im having a bit of a problem that I getting to be a pain to figure out. My wifes 00 SS is stock 00 fbody 6-spd wiring harness etc.. one of my employees borrowed the BCM out of my car and the other car they tried it in fried the body control module (BCM) and I replaced it with another from a 00 Fbody I had laying around.
I dont have the ignition key from the new BCM so i cannot check and see what the OHMS on the pellet security key is so i can just wire in some resistors to bypass it. I did bypass the starter so it will crank no matter what, security cant shut off the starter. VATS is shut off in the PCM as well.
Now the car will occasionally not start and security light will come on. It happens probably once out of 10 times you start the car. It wasnt a big deal for the last month or so because if it didnt start, you just turn key off and back on and it would start right up. But this weekend it just cranked and cranked, couldnt get it to start. Let it sit for an hour, wouldnt start etc. Not till today did it finally start up (first try today).
When it doesnt start, its basically not giving power to the engine wiring harness because it gets no spark. Until the security thing goes away.
So I want to figure out what wire in the PCM pins or where I need to apply keyed power in the engine/body harness to make sure the key cannot disable power to the engine harness.
What wire would I give keyed power to, to ensure the harness is always powered. The easy solution would be buy a new BCM from GM and it will program itself to the key and I doubt I'd have another problem with it, but they are way overpriced so figured I could go around the problem easily
09-22-2009, 12:32 AM
#3
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Pin # 30? Can I just hook keyed power to #30 and that will keep power on in the harness weather or not security kicks on?
09-22-2009, 12:51 AM
#5
I just re-read you first post and saw that you said the VATS was turned off. Now I`m not sure what the problem is, once you turn the VATS off it should not be an issue. There is nothing else that needs to be done PCM wise. On all the conversions I have done I just set the VATS to none in the PCM and its done. Maybe check the VATS again?
09-22-2009, 11:31 AM
#6
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On a factory fbody (wiring harness in original car). When the security system comes on (totally seperate from the engine wiring harness/pcm VATS control), it disables the starter so it will not crank and kills power to the harness and you get no spark on the harness. It doesnt do the start for 2 seconds then die like when you have VATS on in a conversion.
Basically I bypassed the starter kill and i still have no power on the harness (no spark). Its common when the chip in your key goes bad and you have to rig up resistors to fake the resistance ohm on your key. But I dont know what ohm resistance the bcm wants because i dont have the matching BCM to the key in the car. I also cant just start testing resistances till the car starts, since it starts "most" of the time right now.
Basically I bypassed the starter kill and i still have no power on the harness (no spark). Its common when the chip in your key goes bad and you have to rig up resistors to fake the resistance ohm on your key. But I dont know what ohm resistance the bcm wants because i dont have the matching BCM to the key in the car. I also cant just start testing resistances till the car starts, since it starts "most" of the time right now.
