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Morning all, I need help diagnosing a possible electrical issue with my 2002 C5 Z. Ive been back probing wires on engine wiring harness and my LS2 Throttle Body 5V ref wire (yellow) is reading battery voltage when key ON eng OFF. Im no electrical wizard, more like a dummy, but I dont think thats correct. Do I have a short or bad PCM? How would one go about tracing this back to find the culprit? THX!
Here are my TB volt readings: PNK=0V YELL=12.5V BRN= 12.5V GRN=5.0V GREY=0V.
MAF volt readings are YELL=5V.
I do have a Tech2 scanner if I could use that too.
Morning all, I need help diagnosing a possible electrical issue with my 2002 C5 Z. Ive been back probing wires on engine wiring harness and my LS2 Throttle Body 5V ref wire (yellow) is reading battery voltage when key ON eng OFF. Im no electrical wizard, more like a dummy, but I dont think thats correct. Do I have a short or bad PCM? How would one go about tracing this back to find the culprit? THX!
Here are my TB volt readings: PNK=0V YELL=12.5V BRN= 12.5V GRN=5.0V GREY=0V.
MAF volt readings are YELL=5V.
I do have a Tech2 scanner if I could use that too.
I'm sure you have some adapter harness, so you cannot go by wire color.
What’s your issue and where exactly are you backprobing ??…if you need the TPS voltages the connector has 6 wires…2 are your 5 volt references which are dark green and yellow/black… 2 are reference grounds, and 2 are your signal wires…unplugged you should see 5 volts on the yellow MAF wire key on.
Yes thanks for the posts. I'm struggling here trying to determine why my voltages are hi at TPS1 on my throttle body. I even dropped the RPM's to 850 to see if throttle plate opening had something to do with it, but no same readings. It goes into REP mode on rare occasion, but doesn't throw a code....maybe its cause its an LS3 swapped, LS2 throttle body, into a LS6 car with a mix match of sensors, maybe a dyno tune will take care of it?
But I will use these schematics and at least find out if and where I have the problem....and THANKS!
5V ref wire?
