Hate to have to ask this, but I've searched the forums pretty good and only found 1 thread on my issue and I just wanted to clarify. I'm putting new gauges in and I'm trying to wire up a new CEL. I have the wire from the ECM to the light, I'm just wondering if that light needs a ground or a hot wire on the other side. I didn't know if the ECM grounded the circuit when it throws a code, or if the ECM sends the voltage. I was just going to put a test light on it or check voltages, but also thought someone on here could just clear it up for me. The ECM is outta a 87 TPI. 165 ECM. Thanks for the help.

 

The ECM provides a ground. The other side of the bulb should go to IGN switched power. Usually from the gages fuse (PNK/BLK wire).

RBob.

 

Carb / Crossfire ECM's are wired different than factory Carb cars. If your car had a factory Carb and you converted/swapped to fuel injection you'll need to install a "Lamp Driver" to get the CE light to work properly.

 

Awesome thank you man.

 

Here's the Carb ECM C/E light schematic:



Not sure what the color the C/E light wire is on the fuel injection cars...... might still be GREEN/WHITE or might be BROWN/WHITE, but I'm pretty sure it still comes from plug C207 PIN 'C'.