Code Reader/Puller

90 MJ Pioneer I6 4x4 MT

Anyone know of a good code reader or if my Jeep has the built in code reader like other Mopars? I am not sure I have a functioning check engine light- where is it on the dashboard?

Thanks,
PRLJEEP

You're going to need a code reader; your Jeep has a 'Renix' (Renault/Bendix) computer and will not display codes like some later models.

The Renix electronics that you have do not store trouble codes, so they have to be read live. Snap On made an insturment for doing this, but it was several hundred dollars ten years ago.

This is a pre-Mopar system which was developed by AMC (Renault) and Bendix. The good news is that most of it can be diagnosed with a volt ohm meter so you don't have to spend the bucks for a special scanner.

What problems are you having? We might be able to help you narrow it down from there.

By the way, the system did not include a check engine light.

There is no code reader, as there are no "hard codes" stored by the ECU until 1991. The Renix electronics only give realtime driveability data for diagnosis.

If you find this frustrating, tho, I'd be happy to take it off your hands...

Seriously - the old mechanic's diagnosis (look, listen, think) is what works for the Renix system. There is no check engine light, either - that wasn't added until 1991.

I'm not sure if I'd trade the EGR valve for the OBD - at least the Renix seems to have an easier time pasing the Smog Nazis here in California...

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