It may be advisable to peak inside the ECM at the circuit board and look for physical evidence of dark brown stains around the capacitor cans and corrosion.
ECMs of this vintage frequently have leaking capacitors that can cause a bevy of unpredictable problems

Disconnect the battery first.

 

circuit board looks good..

 

maybe this is also where I say... I'm getting trans fault, failsafe, traction, stability, incorrect part, on the info center...

Not sure if that comes into play here or not..

 

Yes, that is an important clue.

Check all the fuses to the ECU and instrument cluster.

With no OBDII, I am starting suspect the internal High Speed network is down.

Do you have an oscilloscope by any chance? Without any history, and with no OBDII to go on, it is a guessing game unless you start looking at signals. The most likely suspects are the instrument cluster and ECU.

The instrument cluster computer is the hub of all communication in the car, and it has a habit of failing from jump starts with a dead or missing battery, so it is also a prime suspect.

 

No oscilloscope. The ECU has been changed.
And I also want to say thank you to everyone who is helping out, I would be LOST with out you guys!!

 

is there are visualy obvious clue to a short if I were to remove the cluster? I'm kind of thinking I may go ahead and get this one rebuilt.. the car does do some weird stuff... can't shift out of park (started after reconnectiong the battery) the rear windows go down by themselves. The battery goes dead in a couple days... and here's the kicker... it is impossible to connect the battery without sparking, so there is a dead short somewhere. I did install a battery cut off switch to minimize this. Without the car running I have to charge the battery often to minimize the sparking.

 

You can find used clusters for well under $100 on ebay. This could be the cheapest path. Based on my experience '97-'99 XK8 or XJ8 clusters will work, but the best odds are to get one from another '98, otherwise you should confirm SW version information which is often not available info from recyclers.

A problem in the cluster is still just an educated guess though..there could be other issues.

 

You can also have yours rebuild.

 

whiteXKR.. your educated guess is better than my un-educated guess and not too expensive. I don't doubt there are other problems but this is not going to break the bank and will eliminate a potential issue...

 

I have ordered a used instrument cluster. It'll take a few days to get here... the waiting begins.

 

I hope it at the very least restores OBDII operation, that will be a big plus for diagnosis. Disconnect the battery before unplugging the old one and plugging in the new one.

 

I hope so too..

 

Ok... I have installed the new/used instrument cluster and the OBD2 scanner still won't communicate with the car... what's next?

Also I can start a new thread if needed to keep problems seprate?

Thanks!
Glenn

 

hello i am have the exact same issues did you ever get this straightened out im dying to know the conclusion