Hello to all,I am new here but have a feeling I will be needing plenty of help on my new to me 88 gta.This car has really been tampered with over the years and really does not run correct at all.But first things first I accidentally applied 12v to the dlc connector terminal f instead of terminal g to operate the fuel pump.(after a 12 hour night shift,LOL)That is the ground control for the tcc circuit.I am curious if i fried something?Could somebody help me out?I looked at the diagram and i would say no but am really not to sure.

 

Hi wayniac , Welcome to TGO !

In this case , no , you did not fry anything , because when you mistakenly applied the +12V to the F terminal , the ECM wasn't actively grounding that terminal . Had you managed to somehow apply the +12V while the ECM was grounding the F terminal (ECM commanding the TCC solenoid) then yeah , you'd have blown the junction in the ECM's transistor responsible for grounding the F terminal . In fact , when the ECM is not commanding the TCC solenoid , a voltmeter on the F terminal WILL show +12V between the F terminal and ground , this will be due to reading the +12V through the solenoid , since the ECM isn't actively grounding the switched negative side of the circuit .