Jaguar XJ - Earth Point Corrosion - multiple spurious errors

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Tue 17 May 2011 13:54
Jaguar XJ - Earth Point Corrosion - multiple spurious errors - 56chevy
Posting this in the hope it will help others diagnose this - it is IMHO a desgin and durability issue with serious consequences but needless to say, Jaguar aren't interested.
This fault can manifest itself as -

Multiple fault messgages displayed which clear themselves after time or on restart (including engine check light, DSC not available, Cruise not available)
Handbrake fault and inability to release handbrake
Headlight or headlights not working
Speedo and guages "die" whilst driving accompanied by multiple warnings - some serious looking (but not correct) like "brake fluid low".

In my case these were traced to the earth points behind the headlights which had disintegrated due to corrosion.

The preventative measure is to check and grease the earth studs.

My local franchised dealer made a temporary repair and advised me they couldn't do a permament one.
Jag CS told me I have to take the car to another dealer soem distance away for a permanent repair at my expense, rather than my local franchised dealer.
The car was out of Jag Wanrranty (but within corrosion warranty) Jaguar refused to consider a corrosion warranty claim.
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Tue 17 May 2011 22:26
Jaguar XJ - Earth Point Corrosion - multiple spurious errors - injection doc

sadly a very common problem on many many cars and often overlooked by mechanics when fault finding. I fixed a vehicle a few weeks ago with almost the same symptons due to s seriously poor earth that had been overlooked by 2 dealers ! one of which had the vehicle in their workshop for two weeks.

The salt on the roads this year was very heavey and sticky as they had added a mix, this has been extremley corrosive on vehicles including all the earth points.

I always clean and grease them but see plenty that are so corroded even on 4 year old cars.

My current experince is that many vehicle manufactures are finding any excuse to bail out of any warranty whatsoever. these manufactures may well suffer long term when customers remember their bad experinceces and buy elsewhere!

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Wed 18 May 2011 08:48
Jaguar XJ - Earth Point Corrosion - multiple spurious errors - craig-pd130

Manufacturers would probably claim this to be an age-related electrical problem, not a corrosion issue ... of course the earthing points will suffer accelerated corrosion because of the connections anyway :-/

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