Engine stalling and other electrical issues

Pablo Technician Nevada Posted   Latest   Edited  
Unsolved
Electrical
Network Communications
1997 Jaguar XK8 4.0L (7 AJV8) 5-spd (5HP-24)
P1798
B1969
B1238
Starter Engages When Engine Running
Stalls

Starter engages when engine running, engine stalls, A/C clutch relay randomly turns on and several other electrical issues.

P1798 CAN transmission control module instrument cluster circuit fault, B1969 compressor clutch control circuit failure and B1238 for over temperature test in the instrument pack…..

Vehicle starts and runs for a short period of time but the starter engages when engine is running, the A/C pump clutch relay commends the clutch on and off, most of my actual values for the engine do not make sense e.g. fuel trims show lean or rich with key on engine off and they keep leaning out and adding fuel before the engine stalls. 

I performed an alternator test and a battery test with the PICO but they passed tests, now I am thinking if one of my alternator diodes is leaking alternating current and causing all these or has anyone has had this issue before. 

any help would be appreciated, oh by the way, according to my concern, stalling issue occurred after battery replacement. 

0
Glenn Owner/Technician
Texas
Glenn
 

Hi Pablo, Make sure to check the trunk and under seat fuse boxes and battery area for corrosion issues. This has all the signs of a poor/ corroded ground. Yes, check for AC voltage in the alternator, these cars will freak out if that happens. The last thing that comes to mind is pull the computer and check for ants. They love electrical circuits and I have dealt with that on 2 jobs in the past.

+1
Ð Awarded
Agree
Pablo Technician
Nevada
Pablo
 

Thank you for the reply, I will test voltage drop on the main components and hopefully I’ll find orrsoion or a lose connection causing all these issues. I appreciate the info

0
Ð Awarded
Michael Owner/Technician
Texas
Michael
 

Check the PCM for water damage, very common on that model year.

0
Ð Awarded
Pablo Technician
Nevada
Pablo
 

Will do so, I appreciate it

0
Ð Awarded