i have a 1998 cherokee and i noticed today that the fan wont come on even when its at 210 and still wont come on when i turn the ac on. i checked the relay and fuse and changed the temp sensor and still nothing. i already jumped the fan and it runs...i have no idea what else it could be and i checked around on the forum and couldnt find anything. any help is appreciated thanks.

 

You can stop changing parts, it won't activate until it's needed. 218°?

 

well what explains it not coming on when the ac is turned on?

 

Is it supposed to? your working on a 1998, right?

 

Yeah 98.

 

LOL

Your AC freon charge may be too low to close the AC Low Pressure Cycling Switch (on top of the AC Accumulator). If the pressure is too low, the switch internal contact will remain open, interrupting the AC Request Signal to the PCM. Without this switch closing you won't get AC, thus, no fan with AC or Deforst selected.

You can either check the system pressure yourself, or have shop do it for you.

There's a simple test you can do to see if the AC Select and AC Request circuits are working and to see if the AC Clutch relay and fan are working.

Remove the electrical connector from the top of the AC Accumulator. Jumper the two pin sockets with a small piece of wire (NOT TOO BIG). On the HAVAC control select a fan speed, turn the mode slector to an AC setting, turn the temp selector to the blue zone. Start the engine. The AC clutch should pull in and the electric fan should run. If your Freon pressure is zero, do not run the compressor too long; running without Freon/Oil will shell the compressor out post haste.

 

thanks alot ill try it tomorrow and see if thats it.

 

Any luck? I have the same problem with my fan