Possible PCM going bad?
09-29-2017, 09:09 PM
#1
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Year: 2000
Model: Cherokee
Possible PCM going bad?
Tried to inspect my car last week and it won't pass because of a check engine light for the radiator fan relay, code P1491. I tried jumping the relay and fan and everything is good. I had this same problem a few
months ago and it went away. It came back just for the inspection, how nice.
I saw a lot of threads about the p1491 code saying the pcm is the issue? Figure I can find one cheap and try it out. What year PCM would be compatible with my 2000 cherokee sport? Would one from a grand Cherokee 6 or v8 work? TIA for the help.
months ago and it went away. It came back just for the inspection, how nice.
I saw a lot of threads about the p1491 code saying the pcm is the issue? Figure I can find one cheap and try it out. What year PCM would be compatible with my 2000 cherokee sport? Would one from a grand Cherokee 6 or v8 work? TIA for the help.
10-01-2017, 04:33 PM
#4
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Year: 2000
Model: Cherokee
Checked the relay and it's good and used a wire to check the system without the relay. Also disconnected the pcm and still no good.
10-01-2017, 08:25 PM
#5
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Year: 2001
Model: Cherokee (XJ)
Engine: 4.0L
I guess the next step is to check the wiring between the PCM and the relay to make sure the wiring is not shorted or broken . and if the wiring is ok then the PCM n be bad . also check the relay if the PCM is bad that it ohms out at spec.