Papote

I replaced the coolant temp sensor on my 2001 Jeep Cherokee because the plug on the sensor was busted and, also, replaced the thermostat because of a recent engine running hot experience. However, after replacing the temp sensor, the engine never got to its normal temp range and my cooling fan wouldn’t come on. I reordered and replaced the temp sensor (same type sensor) but this time I got codes PO0117 and PO118, intermittently, meaning the PO0118 would come on randomly, although the PO0117 would come on all the time. Additionally, the cooling fan would run all the time, probably meaning the computer detected a problem and kept fan running just in case.

Anyway, I tried erasing the code, but it’ll reappear. Even with the engine turned off, the code would reappear after erasing it. I checked the wiring, and all seems to be fine, so I swapped the temp sensors – remove the new one and reinstalled the old one. This time the engine check light stayed off, as it should, which pretty much tells me the electrical system is fine and the new just removed sensor is faulty, leading to codes PO0117 and PO118.

However, the engine still can’t reach normal operating temperature…when view on the temp gauge. And I guess because the coolant temp indication is not high enough, the cooling fan will not operate. The upper radiator hose gets hot to the touch after a little while and I can feel coolant flowing through it, meaning the thermostat is doing what it’s supposed to do. Other than replacing the temp sensor with a different brand name sensor, which I will do tomorrow, I don’t know what else to do.

agreen

Check for 5v at the connector, maybe clean the engine ground points (by the ignition coil) and verify that you have installed the correct part. You could also use an IR temp gun at the thermostat to see if you have a mechanical or electrical issue. Because 120F is awful hot to the touch, and will barely register on the dash.

Papote

I understand if I get “scolded” here for what I’ve shouldn’t done, but it’ll be well deserve. I’m fixing my 2001 Jeep Cherokee so I can put it for sale and decided to purchase a $10.00 coolant temp sensor to fix the issue with the coolant not reaching normal temperature and electric cooling fan not turning on. Well, the first sensor I installed did not provide an accurate reading, so the issue continued, and its replacement provided error codes PO0117 and PO0118.

Early this morning, I went to AutoZone and purchased a $31.00 sensor, installed it, took the Jeep for a ride, and now everything works as it should…the coolant temp reaches normal temp, and the cooling fan turns on as it’s supposed to. I’ve been messing around with this issue for a few days now, but I guess I learned my lesson.