P-ROC

iTrader: (2)

I have an 86 IROC, 305 TPI. My alternator recently shorted out on the valve cover and started a small fire. No prob, new alternator and wires fixed it. Now I am getting a code 15, Low Coolant Temp on my ECU. I checked for an open circuit on the CTS, it checks out good. Voltage side is right where it should be. While checking wires I found that almost all of the wires that should not read anything unless the ECM tells them too are reading .3 volts. I am thinking that my alternator shorting out may have ruined my ECM. Also, when I run a diagnostic check my fan comes on while the jumper is in and doesn't turn off until I remove it. Is this normal, is my ECM bad, or what circuits could cause this?

Saar

the fan turning on in diagnostic mode is completely normal.

P-ROC

iTrader: (2)

Thanks for clearing that up. Any idea on the .3v in the wires that shouldn't read anything according to what I have seen? I was running great until my alternator shorted out.

P-ROC

iTrader: (2)

Good to go. If anyone cares, after checking all of my wires and signals with a multimeter and everything else I could think of I found that the problem was at the sensor itself. I put in a new sensor already so that wasn't the problem. I pushed in on the plug and Wa La. The plug is not making good contact. Temporary fix: I took off the rubber seal and pinched the sockets a little with the needle nose. Long term fix: I ordered a new plug.

bcmag

i believe the make replacement pig tail connectors for these.standard,everco etc.congrats on finding your problem!