Hey guys, thanks in advance for your help. My father recently passed away and left me his Jag, It had not been driven for several months so I wasn't sure if I would need to jump the battery, but it started right up. It generally seems to drive pretty well, but I keep getting random error codes. From the merely annoying (Bonnet Open, Boot Open) to the rather alarming (Air Suspension Fault, Gear Box Fault). They all clear themselves, however, either while driving or by turning off the key. The Check Engine light also comes on and goes off occasionally. Because of the randomness, I'm hoping this is some computer or relay error and not truly indicative of serious problems. Any ideas?

 

Sorry about the loss of your father. I lost my dad a couple of years ago and still have a hole in my heart.
As for the car I would start with the battery. Even if there was enough to start the car it might not have enough to keep the electronics happy.
Read Highhorse's post about the battery. He explains the importance of a good battery
https://www.jaguarforums.com/forum/x...-cures-167063/
Best wishes.

 

Thanks Bob, it would be great if it's something that easy. I'll definitely start with getting the battery checked.

 

Well, I fully charged the battery and it seemed to help, but a day or two later the random error messages started up again. I had the battery tested by two different technicians and it checked out okay both times. The terminals and cables are clean and snug. Any additional thoughts or suggestions would be quite welcome.

 

Please post in the X350 section and you will likely attract more readers to you questions.

I hope you get it running properly.

bob

 

Hi Colonel's Jag,

My condolences on the loss of your father.

I echo the prior suggestions about the condition of the battery. Jaguars require very strong, healthy batteries, and if the voltage sags much while cranking the engine all manner of spurious fault codes can be generated. Most of the inexpensive load testers can't really tell you how your battery is actually behaving while you are cranking the engine to start it. If you have a good analog voltmeter you may get a better idea of how low the voltage is sagging during cranking.

Other possible contributors to your symptoms are corrosion on various ground points throughout the car. The ground points are mostly composed of a threaded stud bonded to the body of the car, one or more wires terminated in ring/eyelet terminals, and a large nut that secures the wire terminals to the stud. The stud, terminals and nut are all made of aluminum, which forms a thin layer of aluminum oxide on its surface when exposed to the air. Aluminum oxide is an electrical insulator, so it interferes with the proper operation of sensitive electronic circuits.

Three important ground studs are behind the front headlights, and another is near the Engine Control Module in the right inner fender near the bulkhead/firewall (right as viewed from inside the car). The link below shows how to clean the grounds behind the headlamps. Other ground points are similar:

https://www.jaguarforums.com/forum/x...2/#post1156791


All of the ground points are identified in the Electrical Guide, which you can download at the link below courtesy of our forum member Gus. I would suggest cleaning all ground points used by circuits for which you've had fault codes. The ground points are shown on the schematics, and their locations are given on the page before the schematic that lists all the components, relays, switches, electrical connectors, etc.:

http://www.jagrepair.com/images/Elec...al%20Guide.pdf

Cheers,

Don