Jaguar XJ40 Intermittent gearbox and engine management light
Jaguar XJ40 Intermittent gearbox and engine management light
Author
Discussion

fast cars

Original Poster:

269 posts

231 months

Tuesday 25th September 2012
quotequote all
The car is a 1992, battery in engine bay model, 4.0 Auto, been stood for some time and now both the gearbox and engine lights come on, but not all the time, when it does the gearbox seems to stay in one gear like 3rd?? but again not all the time, what should I look for on this to try and solve? Any advice greatly appreciated

Cheers

NormanD

3,208 posts

254 months

Wednesday 26th September 2012
quotequote all
Maybe the battery is dying so low voltage

ECU is going into Limp Home Mode

A new battery should do the trick

fast cars

Original Poster:

269 posts

231 months

Wednesday 26th September 2012
quotequote all
Hi Thanks for the advice, will give it a shot, does this mean that the alternator also needs replacing??

NormanD

3,208 posts

254 months

Wednesday 26th September 2012
quotequote all
fast cars said:
Hi Thanks for the advice, will give it a shot, does this mean that the alternator also needs replacing??
Shouldn't do

naki

144 posts

215 months

Wednesday 26th September 2012
quotequote all
the gearbox light is quite a common fault. first course of action is always to check the cheapest and easier thing,
check corrosion and clean the electrical connectors at both ends, so where it plugs into the gearbox (underneath the car). there is a small metal protector outside, remove this and should be a electrical connector then, check the other end at the TCM, which is under the passenger knee bolster. make sure it snot damp/ wet too, as water can sometimes leak in this area and cause electrical damage.

low battery voltage can cause electrical faults as has been suggested. put a multimeter onto the battery and check what voltage is present.

once you have cleaned the connectors, then do a battery disconnect for 15 minutes, then reconnect this will dump the fault code. make sure you have the keys in your hand/ door open, not in the car, as sometimes the central locking can lock itself when you reconnect the battery. you will also need you radio code, if you still have the OE radio

transmission failures are extremely rare on this model of jag particularly, but make sure the fluid is topped up correctly (not overfilled too)
did it drive well before this light came on?

Prof Beard

6,669 posts

253 months

Wednesday 26th September 2012
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Corrosion of terminals on connectors is favourite, I agree. I've even seen this problem solved by cleaning connectors on an episode of Pawn Stars!

fast cars

Original Poster:

269 posts

231 months

Friday 28th September 2012
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Thank you very much to you all, I will give this a shot and hopefully does the job, BTW 'Naki', whats that Insignia like?

naki

144 posts

215 months

Sunday 30th September 2012
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fast cars said:
Thank you very much to you all, I will give this a shot and hopefully does the job, BTW 'Naki', whats that Insignia like?
have a look. its a truly unique car, at a bargain price!

http://www.ebay.co.uk/itm/280974280024?ssPageName=...