Check engine re-wiring?


Frequent Racer
Aug 27, 2008
Spring Hill, FL
I'm trying to rewire the check engine light to come on with the LS computer, but can't figure out what wires to cut behind the instrument panel. Anyone got a source for the pin-outs.


Jun 2, 2003
Catalina, AZ
Looks like this schematic shows the check engine light... best bet if this doesn't work is to just follow the traces on the cluster. Not the easiest thing to do, but it's also not rocket science 8) At least this will give you a wire color to look for. I don't know how the LS computer illuminates the bulb, but you may have to some minor rewiring if it puts out +12v instead of supplying a ground.

Another thing, is there actually an SES terminal on the LS computer?


Frequent Racer
Sep 21, 2003
Here are the wire colors to look for. I bought a round guage style dash that came with the connector with wires cut off. This is what I found. (I don't remember what the dash pod came out of.) The power side of the CEL is just a fused +12V. Then you just ground the other side to turn the light on. You can see in Doober's print that it says it is brown with a white stripe. I found a yellow wire in the location. The pin number of the connector should be accurate though.

Actual data from a Dash

Pin - Cir Num Wire Color Signal

10 - 489 Yellow (Pass thru) CEL (Ground to illuminate)
11 - Pink, Black stripe Power side of CEL

Similar threads