Battery Leads

[jeff1954]

As I have mentioned in previous post,s electrics are not my strongest point but I read with interest in this months mag Andy Carruthers article on X Type electrics. Especially the part about disconnecting both battery leads and touching them together to clear problems.

Would this procedure work on my 2004 S Type, as I have on start up for a split second a warning light and message saying ABS fault, when I know the system is working correctly. I have changed the brake pads in the past and this could be why the indication has occurred.

Jeff

[J44EAG]

In ten years of S-type ownership. I`ve never touched the two leads together to clear a fault code although I have heard it said that this method can work. Just disconnecting the +Ve terminal for twenty minutes will do what is known as a "hard dump" and should clear any old fault codes.

In my experience the spurious DSC code comes up sometimes if a battery is weak after a start up. This can cause the diagnostic facility within the car not to complete correctly and strangely the light comes on. If you then run the car for a few minutes to give the battery a half decent surface charge, stop the car and restart again, you will often find the light goes out on its own accord. Clever, eh? This odd side effect of low battery condition is a well known one on our BB network and does not just affect S-types.

The electronic architecture did change slightly on the pre-facelift models onwards so perhaps the flash of the light might be part of the design. If the light goes out and stays out, you probably don`t have a problem.

Relining the brakes should not have changed anything by way of DSC parameters even though there is the so called electronic handbrake tacked onto the braking system.

Mike

[jeff1954]

Thanks for that Mike. Do you think it would do any harm if I tried it.

Jeff

[J44EAG]

I don`t see the point of taking the risk. Touching -Ve and +Ve leads together creates a risk if residual voltage is stored in high tech components which may have inbuilt capacitance remaining. It goes against the grain for me. Try it if you like but if something then goes pop, you have another problem....self inflicted.

Why not just disconnect the +Ve lead for twenty minutes? This is a known and tried method of clearing codes.and stay safe.

Mike

[oldtimer]

Jeff,
It could be possible that you take out one or more micro processors ,that would really make your day

[Montana5]

This method of hard reset is done all the time by Jaguar Owners and is perfectly safe, it is like resetting all the variables back to default settings, as they would have left the factory, many people claim their Cars run better after a reset. You will need to reset the Radio, Seats and Door Mirrors etc afterwards.

(When I worked in the Telecomms industry we used this method of reset when fitting new software to the various Power & Battery Systems, this insured a clean memory wipe before loading the new adaptations)

Doug.

[jeff1954]

Hi Doug Have you done this procedure on your car?

Jeff

[Montana5]

Not had the occasion to do the reset on my own Car yet Jeff, though when the time comes I won't have any hesitation in doing it.
If you are still unsure about doing this, why not firstly try a 30 minute total Battery disconect to see if that clears the warning light.

Doug.

[jeff1954]

It's not that critical that I have to do this as like I say the ABS works fine and the message only comes on as I say for a split second. Also I would not like to compromise the Re Map I had done some years ago by doing doing this procedure which could have the same result as a ECU Re flash.
As I have said before electrics are not my strong point so I will take on board any advice anyone gives me.

Jeff

[jeff1954]

Sorry but I forgot to put in my last post that I have done the Neg lead off the battery a few times in the past for other issues but this split second message still persists.

Jeff