Hello I know there are several threads on this subject but here's hoping someone has an idea what is going. My 2005 XK8 x100 convertible no longer operates from the keyfob. The fob has been tested and is working. and is programed to the car. but it is not responding. I removed the SLM from the car cleaned the contacts opened the circuit board and cleaned the connecting ribbon between the 2 boards reconnected the slm and bingo all worked central locking ,lights, boot release,tried it several times all good, took the car for a quick drive before parking her up got out and nothing, back to square one. Connected a I carsoft obd and it shows a fault in the SLM U1041 SCP vehicle speed signal invalid or missing can anyone help its driving me nuts.
Dave.

 

The first question will always be about the condition of the car battery.

 

battery is brand new

 

what’s the battery voltage after sitting overnight with the engine OFF ?

anything less than 12.6 v means you need to keep a battery tender on the car when it is parked overnight or longer.

The wiring and electrical circuits on these cars are not the same as when new. There is more resistance to current flow. The battery has to be 101% to avoid a myriad of electrical gremlins.

i use to have random spurious electrical faults and issues including ENGINE FAILSAFE and RESTRICTED PERFORMANCE.

After following the forum advice to use a battery tender I’ve had zero electrical issues. The NOCO Gensis and CTEK brands are very popular.

Z

 

Thanks for that just checked battery the car has been sitting for a couple of weeks voltage is 12.4v so I have connected a trickle charger and will see what happens overnight.
Dave

 

If the battery tender doesn't make any difference, then try operating the fob as close as you can get to the SLM - in case there is an issue with the antenna.

For the sake of good order, I'd recheck the output of the fob to confirm it is still operational (just in case). Do you have two button cells in there?

Absent any other SCP issues, I would ignore the U1041.


Not your issue in this instance, but be aware that the SLM goes into a 'deep sleep' mode after ~28 days, so requires a key action to wake it back up.

 

Battery now at 13.4v still no response from the fob Ive held the fob next to the slm no response,there is only one battery that goes in the fob. What I cant understand is why it started working after cleaning then packed up again when I took it for a drive. Thanks for all replies
Dave

 

Sympathise. Intermittents can be a real pain to resolve. Perhaps disturbing the connectors enabled a brief period of sanity before falling back into fault mode?

Long shot:- one other possibility, although I'm not sure if this holds true for late cars, is that the fob won't work if the key is in the ignition (confirmed for my car). There's a spring-loaded flap on the key barrel that can stick open, mimicking a key-in position. Check that it's closing properly (about 3/4 closed) when you pull the key out.

If it's lazy, try squirting some graphite powder in (watch out - that stuff goes everywhere...)

 

Many thanks for advice the flap seems to be working ok also had keyfob rechecked and its working ok.As the car isnt responding to any of the functions of the fob do you know the difference between the 2 circuit boards in the SLM the smaller one has the antenna attached to it then there is a ribbon connecting the two boards wondering if that ribbon could be damaged.or the connections.

 

The smaller board is the radio receiver for the fobs - it would certainly be worth checking the ribbon cable very carefully. If you do open the SLM again maybe post some good quality photos on here to see if anyone has any other ideas.

 

Probably retracing old ground, but you could try re-pairing your fob(s). I very occasionally had to do this before the car sat on a tender.

See attached.

 

You probably ought to read this thread.

https://www.jaguarforums.com/forum/x...=key+fob+range

Although it starts with v short range of fobs, the solution is likely the same - either a replacement SLM (Ludicrous prices for used 2005 type or a repair of the one you have now. As you're in UK I have no hesitation in recommending Berkshire Jaguars. Call by phone to get current prices or use this link

https://redirect.viglink.com/?format...bd-c2x27169675