What I stated above is for the 96 truck and the N/S switch didn't go to the VCM like the newer pcm, I think it actually coded off the circuit to the VCM. I'm going to go back through my data to see how I hooked mine up because I don't remember going through the pcm pin 34 orange/black wire, I can't remember.
Last edited by NITROUS; 08-12-2008 at 09:27 PM.
97 GMC, 2002 LS6.
1991 GMC Syclone #1428
VATS is really only specific to the systems that have chip keys.
You have a security issue I'd say. A noid would help a lot like said above. Sensors rarely gay out like this. Something else is wrong. Remember, there are more modules and "thinking" involved on the security system than just the PCM. Someone's not happy here and I'll bet it's the BCM, etc. 'cause I bet you can't read body codes, eh?
right now i'm not getting any codes back but the red light on the diagnostic is lit. I'm leaning towards the PCM also.
1996 GMC extended cab, 2003 5.3/auto
I have a feeling the VATS wasnt removed.
If we connect the crank solenoid wire from the new computer to the starter, nothing happens with the key in start position.
Will his pcm work in a 2000 model truck with a 5.3?
You need to search local car lots, take an 03 for a test drive...haha
Last edited by LSXmyford; 08-13-2008 at 06:39 AM.
LSX conversions, so easy a caveman can do it.
Originally Posted by GasGuzzler
What 468blazer forgot to mention, earlier he stated that pin 12 CKP, shown no voltage. It was expressed that this is one sensor that needs 12volts. He replaced the crank sensor, and cam sensor. Currently, there is positive voltage at this pin, so it seems to have been an issue.
LSX conversions, so easy a caveman can do it.
A DBW PCM will not work in a DBC vehicle, it needs the throttle pedal electronics.
See my truck data in the "My Garage" section here... http://www.ls1truck.com/forums/my-ga...tml#post191709
gotchya.
He has a buddy that works at chevy as a tech, he should be able to test his PCM correct? Will he need the VIN or any other info from the donor vehicle?
He should be getting a noid test light too. What I realized, weve been cranking the starter directly from the yellow wire, bypassing the neutral safety switch. On the plus side, we found out that two sensors were bad (one crank one pedal position), but still no fire, hopefully, hopppppppppefully, once he reconnects the yellow wires, and connects the purple wire from the original harness to the starter solenoid, she'll fire...not really optomistic at this point as when we tried that before, the engine wouldnt rotate...which led to the whole VATS not removed theory....ever feel like your chasing your tail?
Last edited by LSXmyford; 08-13-2008 at 08:54 AM.
LSX conversions, so easy a caveman can do it.
The VIN is stored in the PCM. Don't let him change or reload the tune. Just verify that the VATS function has been turned off.
Last edited by RedHeartbeat; 08-13-2008 at 09:04 AM.
See my truck data in the "My Garage" section here... http://www.ls1truck.com/forums/my-ga...tml#post191709
There's really no way I know to bench test a PCM with exception of the aftermarket tuners. I think what was said earlier was the MAF is one of the only 12V sensors as most are 5V. The CMP and CKP are 12V also.
Here is where we are at now, its actually where we began.
the yellow wire has been reconnected to its other half. he then took the purple solenoid wire (from the old harness) and ran it to the starter, turn the key, nothing happens. which is odd, as his truck was running fine with the old engine installed, so this solenoid wire should activate the starter fine but it doesnt.
just for the hell of it, he tested the solenoid wire on the new pcm with his multimeter, to see if he would get 12v with the key in start position...nothing.
otherwise, he is getting power at the PCM where it should be and the fuel pump relay on the new harness is clicking, as it should.
this is with the new harness connected to the Neutral safety switch (NSW). for chits and giggles, we even attached the old NSW to the new harness connection, then we connected the old and new NSW to the old harness NSW connection...nothing.
Last edited by LSXmyford; 08-13-2008 at 10:49 AM.
LSX conversions, so easy a caveman can do it.
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