• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

unable to pull codes?

RiXJeeper

NAXJA Forum User
Location
Detroit, MI USA
So I just dropped a remanufact. engine into my 2000 XJ. Runs fine on start up but after it gets warm runs a little rough, almost like a misfire. I have a check engine light but when I plug in the code reader I get nothing. I know the reader works, but it wont get a signal from my XJ. Any way to read codes without it?
 
I dont think you can get codes from a chrysler ecu obdII with out a reader. you might have to take it to some one who has a nicer scanner who can data map and do real time drivability tests via snap on modis or whatever......(ridiculously expensive scanners) Try lookin into whether the ecu is bad because it is not responding to to an open loop operation (when the o2 sensors warm up) compared to closed loop which is a default tune in the ecu when the engine is cold. Other than that I dont know..... Good luck!
 
That scanner has to get power from the car. I don't know which circuit it gets power from on yours, I know GM frequently taps into the cigar lighter and if that fuse blows it wont scan. I would check fuses and if you have things such as cigar lighter not working I would start there. It is probably getting signal just not power. HTH Don
 
I have the exact same problem from the exact same situation (engine swap). The OBD-II reader turns on, but when connected it has actually caused my odo to read 'no bus', then the engine roughs out and stalls. The ODB-II tool I rented runs on batteries, so power is not an issue.

I think I may need to find a nicer reader anyway, as I need to confirm the placement/angle of the camshaft position sensor - none of the orientation marks I had were transferrable to the new block.

From my research I'm stuck trying to find someone with a DRB-II or DRB-III tool, which is super expensive and few shops outside of dealers have. Unless of course someone else on here has a better solution.
 
check ground and power at the obdii port. i forget what pins are the ground and power. but i had the same problem, it was a bad ground.
 
OBDI you need a power source, OBDII should be a powered connection.

As XBoBJ said, check the power and ground.

Note: A shorted to ground CPS/CKP has been reported to prevent the scanner-PCM connection, but if I remember those posts correctly the vehicles were in a no run state.
 
Back
Top