After a battery disconnect, my key fob stopped working. Have to hold the fob under the dash to start the car. Same problem with the spare, and also with a new fob battery. Car is ok to drive, but I can't lock the doors. (The car doesn't even double chirp when I try pushing in the handle.)
Any ideas?

 

If both keys have stopped working as remotes then it's lost it's programming somehow...

This is what warranties are for, off to the dealer!

 

Not sure if it will apply to Jags but I know on some Rovers, if the keys or the KVM don't reprogram, then the KVM, keys and CJB need to be replaced. Typically happens if the owner lost both smart keys and the new replacements won't program.

Hope this isn't the case for you!

 

What are the KVM and CJB?

 

A few years back there was literally a crime wave of new Range Rovers being stolen in the UK, the thieves were programming new keys and driving off in the cars.

JLR's response to this was to revamp the keyless entry system and part of that is you cannot program "new" keys to an existing KVM (Keyless Vehicle Module) the module has to be replaced with a "virgin" one any time a key needed programming.

CJB = Central Junction Box, basically one of the major modules on the network that handles vehicle configuration.

I can't really imagine why it would suddenly stop working, but I don't think it would have anything to do with engine tunes if that's your concern...

 

Cambo is correct. Are you getting the message on your gauge cluster that says "Smart Key Not Found"?

 

I wonder if there are any fuses which might have popped? Worth checking...

 

That happened to one of my keys, just stopped working. I brought it by Jag to program and the Service Adviser said that happens from time to time. I hope it doesn't happen after the warranty is up.

 

Both of my keys no longer work.

 

I'll take a look.

 

Easier said than done. I need to check F8 in the fuse box below the left side A-pillar. 1) The access door is about 1/3 the size of the fuse box. 2) the access door can only be held open when the clutch is fully depressed. Try depressing the clutch while simultaneously holding the access door open and removing a fuse located in a blind spot with only 2 hands while contorting yourself to get your upper body under the steering wheel. It ain't happening. BAD DESIGN.

 

Missing sticker - No User Serviceable Parts Inside ;-)

 

KVM needs to be replaced.

 

Do you think frequent battery disconnects have done that or was it just a failure waiting to happen?

Larry

 

Damn...

It should be covered under warranty, I don't see how they could argue it's not.

 

Must have been the sonic booms that Lance's car frequently produces.

 

Just a failure waiting to happen...all of these modules should be able to withstand ongoing battery disconnects. Attaching a battery charger or tender to the battery while it's still connected,or jump starting off another car might cause a spike that could destroy modules, but I've never done any of that.

No resistance from my dealer at all. They were just chagrined that they can't get the part until tomorrow. I go back then and I get a loaner.

No... the problem occurred right before the first tests of the headers and 200 cell cat downpipes (and those produce some real sonic booms). I am certain you heard us fire it up yesterday. Promising results, but the tune is being adjusted to get full benefit from the headers.

 

My telematics module fried after a battery disconnect / reconnect causing a service light to come on. It was replaced under warranty because I played dumb and never mentioned the disconnect. I am convinced that there was a surge when I reconnected it that caused it... there's a pretty good spark and "pop" that comes off the ground when you reconnect which I read is the result of the many systems drawing current.

I had done a few disconnects with no issues prior to that episode... however, when I fried the module the battery had been on the charger for awhile and was fully charged. I wonder if having a fully charged battery had anything to do with it?

At any rate it makes me a little nervous about doing it again.

 

I am curious if your problem is related to the problem I have lately. When I get out of the car and I hit lock on the fob the car does not respond. Then after a bunch of clicking and roughly 30sec-1min the car will finally decide to respond and lock, but I don't get a chirp when I double lock. Its super random and intermittent, but it drives me crazy when it happen.

 

Just for grins, try changing the fob battery.