2000 b1500 pcm, input, or connection problem


car56
05-25-2008, 04:16 PM
I know this is a stupid question, but does anyone know where I can get my hands on a schematic for a PCM for a 2000 5.2L b1500 van? Alldata has an elementary one, but I can't even read it. it's so small. My van runs fine, then starts bucking and misfiring, then smooths out(I believe it's going into closed-loop mode, or limp-in mode). I changed the cam sensor, no luck. My ASD and fuel pump relays are getting voltage sporadically, and a few times I swapped the relays and it was fine. I'm checking the rest of my grounds and connections tomorrow, but I need to know which wire feeds the crank and cam sensors so I can check to see if they're getting 5 volts. Thanks much

alloro
05-25-2008, 05:23 PM
Do you mean that you want a schematic of the pcm itself, or are you just looking for the pinout?

car56
05-25-2008, 06:11 PM
Hi, I was hoping(I know, crazy, probably only factory authorized) for the pcm schematic itself, but the pinout would be better than what I've got, thanks.

car56
05-25-2008, 06:14 PM
Actually, I disconnected the battery ground and computer and sensor grounds, and cleaned them, and now the relays kick in but the IAC(or whatever controls the idle) won't let it idle and it just turns over so slowly that it dies.

alloro
05-25-2008, 07:37 PM
Will these help?

http://usera.imagecave.com/ydfah/vehicles/C1.gif
http://usera.imagecave.com/ydfah/vehicles/C2.gif
http://usera.imagecave.com/ydfah/vehicles/C3.gif
http://usera.imagecave.com/ydfah/vehicles/Schematic.gif

car56
05-25-2008, 07:47 PM
Yes, thanks very much, I think this should put me over the top! I hope I can return the favor, I also hope I can get my van to run! Thank you again!

newmans auto air
09-16-2009, 09:41 AM
im haveing the same problem,i have used the same schematic.there is 5 volt ref on tps and crank and map on mine.the auto shut down relay is shutting down the power to the ignition coil.it gets ground but not power.i have changed relay.im stomped to.

alloro
09-16-2009, 10:01 AM
I'm having the same problem, I have used the same schematic. There is 5 volt ref on tps and crank and map on mine. The auto shut down relay is shutting down the power to the ignition coil. It gets ground but not power. I have changed relay. I'm stomped too.

I'm not quite following you. Since the ASD relay is shutting down power to the coil, it means there was power there when the key was on...correct?

newmans auto air
09-16-2009, 10:18 AM
well it runs fine untill it warms up.then it shuts down and will not run for hours,all gages quit and bus comes on odometer.i guess im checking it right.i pull the asd relay out and test with meter,im getting 2 powers and one ground and nothing out of other terminal.i checked the plug at ignition coil and im getting ground no power.can you help me alloro

alloro
09-16-2009, 01:32 PM
well it runs fine until it warms up.then it shuts down and will not run for hours,all gages quit and bus comes on odometer.

These are classic symptoms of a bad computer. The computer is also what controls the ASD relay. So a bad computer would also explain why the relay is shutting down.

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