hi i have a 93 si hatch with a 94 b18c1 and my cel is on. When i turn my key to on the light doesn't come on, but when i start it it comes on. When i try to check the codes nothing happens. Any help would be great. Thanks

 

When checking the codes does the light just stay on after you put the jumper in? If so you need a new ecu.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SpeedFreak77 &raquo;</TD></TR><TR><TD CLASS="quote">When checking the codes does the light just stay on after you put the jumper in? If so you need a new ecu.</TD></TR></TABLE>NO! It's supposed to stay lit constantly (with the jumper in place) if there's no error codes stored. Code zero (bad ECM) is when it stays OFF when you put in the jumper.

Check the wiring for the CEL, maybe it's not hooked up correctly with '93 car & '94 ECM? Also check whether the plug you jumper is connected correctly to the ECM. Don't be so quick to say the ECM is bad.

 

when i turn on my key there is no engine light. When i start my car the light comes on. i turn my key to the on position and it just stays lit when i jump it. I will check my wiring later. And it's a obd-1 p72 ecm. I will try my p28 to see if that works.
Thanks

 

Maybe this can help you check out your wiring...

CEL is always powered from the main relay. The ground side of the bulb circuit is switched by ECU pin A13.

ECU pin D4 goes to the SCS connector. When you jumper that plug, what you're really doing is connecting D4 to ground.

 

When i turn the key to on, and jump there is no light now.

 

What did you find when you checked your wiring? Does the CEL have it's power? Does it come on for it's bulb-check or not at all? Continuity in the wire from CEL to ECU A13?