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Jdperk-86elco
April 28th, 2006, 09:22 AM
My TCC brake switch input (pin 33 purple if I am not mistaken) is reading 10.4VDC with the wire isolated and ignition on or car running. The scan shows this input "Applied" could this input be bad?

Is my only course of action to get a new PCM? This is causing my cruise to lock out. This is a new swap and the car drives fine and I guess the PCM is compensating for this input being bad. I have yet to get the cruise to work and I installed the Corvette drive-by-wire system.

Any ideas?

joecar
April 28th, 2006, 11:19 AM
Using a 1k resistor on the end of the wire, short it to ground and then to 12V, and each time see if you get any change on the scan tool.

If you get no change, then unplug the PCM connector(s), locate that wire's pin, and test the wire's continuity with a multimeter (may need a buddy to hold one of the probes); also check for short to power and to ground.

If continuity is good and wire is not shorted, inspect the PCM connector plug/socket for damage or foreign objects.

If that seems ok, then PCM may have a bad input.

It won't hurt to check the ground to chassis connections in engine bay.

Jdperk-86elco
May 2nd, 2006, 03:13 PM
I found the problem. The TCC Brake Switch input was on pin 34 and it should have been on pin 33. I moved it to the proper pin and the cruise control worked perfectly.

Just a simple mistake from the harness builder, who by the way helped me solved this issue.