PO118 engine coolant temp sensor problem
Thread Starter
Joined: Apr 2008
Posts: 1,616
Likes: 4
From: Fort Worth Texas
PO118 engine coolant temp sensor problem Car started throwing this code, I looked it up in the manual, I replaced the temp sensor, with a new one from GM. It is the 3 pin sensor, 5 volt Signal wire from the PCM ( I tested and have the 5 volts) then a ground wire, then one going to the gauge. With the new sensor I am still getting this fault. I clear it with my scanner but pops right back. I removed the clip and the PCM connectors, I OHMed the signal wire back No problem, I ohmed the ground wire back, No problem, I ohmed the PCM ground wire to the ground on the car, and its fine. I ohmed the sensor clip ground wire to a ground and its good,, Any Ideas on what can be causing this fault?
Last edited by RARON455; Jan 27, 2011 at 07:43 PM.
Thread Starter
Joined: Apr 2008
Posts: 1,616
Likes: 4
From: Fort Worth Texas
Problem solved To any interested,,, I went and bought another sensor, I put it in, same damn thing..So I Just plugged the first sensor I bought in and left it hanging, and everything was fine scan tool showing correct ambient temp, Then I plugged back into my second sensor, and fault showed back up, scan tool showing -39 which is the default. SO I had an idea. I pulled and twisted in the clip that was plugged into the sensor, and there you go, the fault was gone and engine showing 191 degree temp, all is fine. So the problem was actually in the clip, I gues when I plugged it in it has the problem, but unplugged no problem, thats why all the test I did with my multimeter passed. Problem is the damn clip..Solved.
