Suaveat69

Fans don't come on unless I turn on the AC or defrost. I checked relays with the CHMSL and they are good. Also checked both 30a fuses and they are good.

Only thing I did not check was the fan harness yet. Could the temp sensor be bad since this is independent of the AC commanding the fan on?

Jesse

iTrader: (4)

CHSML is the third brake light. What temps are you seeing that make you concerned that the fans aren't coming on? They don't really kick in too much until 205-215* or more. Also if the temp sensor was no good then the fans would be on 100% of the time, not the other way around.

Suaveat69

CMHSL is the same relay as the fans. Usual temps are around 195. I lit it idle until 218 and the fans did not kick in.

The temp senor commands fans to kick on @ 215 so if the sensor is bad why would it command run all the time?

Jesse

iTrader: (4)

Arr you sure they aren't spinning or are they just not audible? Typically if the car can't reference what temp the coolant it, it commands the fans to 100%. That way the car won't overheat. When you turn the A/C on, it will reference AC Pressure to command the fans. That makes them come on more aggressively. Here's a pic of the fan logic vs Coolant temp in an LE5. LSJ and LNF slightly different. I'm assuming the info in your profile is right about you having a 2008 Sport model, which is 2.4.

Suaveat69

Thanks for the chart. I looked at the fans spinning when I hit the AC. I will let it idle until 220+ to see if the fans do come on and will check and clean the harness. Makes sense on the temp sensor so I can rule that out.

Suaveat69

Fan came on at 225. Must have been since the rad was just changed??

jimbofug007

https://www.cobaltss.net/forums/gene...g-fuse-312065/

The 2.4 has a low pass resistor. Mine only turns on when it has to because I haven't changed the resistor

Sl0wbaltSS

Mine comes on high at 198 from what I see. low is usually 195.