OBD2 not reading / New Member

Hello, I'm a new member with a question. First off I'm a Jeep guy but old Jeep (cj2a) this is my wifes XJ. It's her second one and we looked long and hard for this exact Jeep.

I've never had a problem with it I can't fix but this one I just wanted to ask some guys more familiar with this model.

I did a search and read a few posts before asking my question just to make sure it's not a common problem, and got a little info but would like more.

Ok here we go, 99 XJ Sport 4.0L auto selectrac. Starts, runs and drives fine but the check engine light comes on intermittently (no biggie right) well my OBD2 code reader says "unable to connect". Now it works fine on my truck and a friends car but not the XJ. I disco'd the batt to get the check engine light out to pass inspection (safety only).

Whats the diagnosis? Oh and give me the dummy version.

Thanks,

Matt

What kind of code reader are you using?

What about a run to the local Auto Zone etc.? That would let you know if it's the code reader or the Jeep.

Im not sure by any means, but its possible that the fuse thats in the circuit that your diagnostic plug is in, may be blown. I havnt had this problem on a cherokee before, but on a sierra i couldnt connect, but i could on my other vehicles. I replaced the fuse on the circuit and i could connect after with no problem. Anyway just a suggestion good luck with it.

Hey thanks for the respones!

It's an Actron CP9175 OBD II AutoScanner
It works on all other vehicals
Jeep won't scan at Auto-Zone
I checked all fuses even the ones under the hood.

Are your gauges working OK? What about your odometer? Any odd electrical issues?

I ask because it sounds like you have an electrical gremlin. Loose connections under the dash can present all kinds of weird symptoms.

Also, get a strong flashlight and check the connector.

Everything works fine, once and a blue moon the gas guage reads empty then will read normal. No other electrical issues. I've done checked the connection, plug and receptacle. All look good.

quote : Also, get a strong flashlight and check the connector.

which connector, in-case I've missed something.

I meant the OBD connector. Sounds like you've done that.

ive got a 98 and i dont know how proficient you are with wireing but ive got an alldata sub. ill email ya my password and logon name if you want to try looking there i have no idea if it is there[the diagram] or not also have you checked the plug for 12volts with a meter in any of the plugs? [email protected]

Sweet! thanks for the offer. I had an alldata account for my wifes old Passat (maint. nightmare).

btt