lastmanstandin

Sorry for bringing up a old post but how can someone pull the codes of a 90 XJ with no check engine light? Theres a plug with 4 wires under the dash but I couldn't find a scan tool that would hook up to it....

losingxinsight

I wanna say 90 should have a light....but I'm probably wrong. I think renix stopped in 89? Not sure.

JerseyJeeper

Located mine and pulled it out lol no more problems

BlueXJ

No CEL on anything older than '91. Renix years stopped with '90. After that there was OBDI until '96 then OBDII. Both OBD types have CELs but prior to that no CELs are built into the systems.
There was a scanner made to fit the Renix years but it is long out of availability and since Renix stored NO codes it could only diagnose what it was seeing in real-time.
HTH
Blue

losingxinsight

I thought that they would have the check engine lights once renix stopped, guess not.

JerseyJeeper

^ So did I

lastmanstandin

I found this...
Sounds like a stupid system if you can't find out whats going on with it....

The Renix control system is "pre-OBD," and therefore does not have a "Check Engine Lamp". It also does not "store" or "throw" Diagnostic Trouble Codes (DTCs) or "Parameter IDs" (PIDs) - see: OBD-II PIDs. [5] This is a common problem at vehicle inspection, particularly in California and other jurisdictions with emission standards. Most inspection stations are not aware and will try to explain that the CEL/MIL "doesn't work" (note: there may be a cutout for it, but no bulb). It is recommended that the inspection technician be shown the "OBD Exempt" federal emissions label (located under the hood) and/or have the factory service manual as a reference to avoid this problem.

2.5TURBO

The computer you need to hook up to the renix system(87-90) and the 84-86 systems is only at the dealer. There are 2 little yellow plugs under the hood near the firewall. One is half the size of the other.

I went to the local auto parts store and they told me "i'm sure it's there you just have to find." YOUR AN IDIOT! is all I could think.

I have access to that dealership computer and it didn't help with the problem I had with my renix. So that one got scrapped and I bought a 92. Thank god for OBD-1

Flint Reyes

XJ 88-90 has Renix system that utilizes the Chrysler DRB II scan tool. OBD scan tools will not work with the Renix system. Though manual diagnostics of sensors using a volt meter is possible.

2.5TURBO

Where is the accurate information with what all the volts are supposed to be?
Finding that info is like a needle in a haystack!

Flint Reyes

Hi there! Check out this link.

http://www.lunghd.com/Tech_Articles/...iagnostics.htm

2.5TURBO

hell yea, that's some useful stuff. nice find!

lastmanstandin

Update:
Mine was loose bolts on the intake....

ol red

my emiss maint light is on to so would that be cause a vacume line on my 4x4 not working or hego

n91chriss

I don't want to hijack this guy's thread, but I was wondering if any of you knew how to retrieve trouble codes from a 1988 Renix-type 4.0L? I can't tell if it's supposed to/has to have a scan tool on it, or if a sequence of check engine flashes was supposed to be the way on this year/model.