Re: check engine light wiring
Reply #6 –
If you had the base cluster in there before, the needed wires should already be in the plugs. No digging around tracing wires from the EEC to anywhere.
The bulb would have originally gotten power from incoming wire A6 (Grey plug, red/yellow, fuse #18), and been grounded by the EEC or the ignition switch "start" position via outgoing wire A7 (tan to test plug, tan changes to black/blue at ignition switch, yours is all black/blue?).
Does your new cluster have the Check Engine light connected through the plastic overlay, or is it the separate bulb/wires/plug style?
That will be the "Signal Return" from the various sensors, and has nothing to do with the light.
I have another wire list here (possibly wrong) that shows a black/white from B18 (brown plug) as the speed sensor ground.