What might cause a 1994 Jeep Grand Cherokee Ltd to keep blowing the 20 amp fuse that controls the AC compressor?

Answer 1

I had this same problem on my 97 Jeep Grand Cherokee. It was a problem with the O2 sensor. Check the wire and connector to both your o2 sensors {there is one before the muffler and one behind it}.

The new o2 sensors are expensive, to the tune of 80 bucks or so. The connector that plugs into the sensor got mangled somehow {the wires were too long and there was no bracket to keep them in place}. I ended up cutting the connector off both sides and soldering the wires to the new molested o2 sensor, then replacing the 20a fuse again for the 3rd time.

This truck wont run at all without it's o2 sensors in perfect working condition. There are too many other things it could be, but I'd check all your wiring and make sure there is no shorts anywhere.

Answer 2

There is a dead short somewhere. If there has not been any damage to the vehicle to cause a possible short it is a process of elimination. Battery cable touching frame? Disconnect the heavy wire from the back of the alternator and see if it blows. Amp for the radio? What doesn't work when the fuse is blown? With the key in the on position you should be able to narrow down the posibilities.

Answer 3

If it blows the second you try to switch to ac it's probably the coil in the ac compressor.