2008 Vandana plus, I was at a light and then I heard big thump under my butt. All of a sudden, the dashboard lit up saying dsc was unavailable and gearbox fault. My screen kept blacking out. I got home turned the car off and now it won't start. When I turn the key the car clicks, engine doesn't turn over, the speedometer and techometer needles bounce around.

I'm thinking this is more electrical than the gearbox but it could be hope as well.

Please advise.

Thanks,
Fernando

 

I let the car sit for about 10 minutes. It restarted however 8tnsounded like it had a weak battery. The gearbox fault was gone but it said that the cruise control was unavailable. The battery is about 5 years old. I've heard that the cars are finnicky without full voltage. Has anyone seen this first hand

 

Get a new battery.

 

+1

 

I would check for corrosion on the battery terminals before replacing the battery. I've had similar symptoms on other cars before. There doesn't need to be any visible corrosion to have an issue between the terminal and the clamp.

Dave

 

RT-MG wrote

would check for corrosion on the battery terminals before replacing the battery. I've had similar symptoms on other cars before. There doesn't need to be any visible corrosion to have an issue between the terminal and the clamp.


Good advise, always keep both terminals clean.
Cruse Control not available, tells me a weak battery.

 

So I took the battery in and it was at 35% charge so they charged it and tested it and it was fine. I put the battery back started the car connected a multimeter across the positive and negative and it read 12.4v with the car on. Has to be the alternator correct?

 

At 5 years most batteries fail the "cold cranking amperage" load test. Actual voltage reading doesn't tell you of the battery's overall condition.

 

But it does tell me about the alternator correct?

 

12.4 seems low. I have been chasing a charging issue for years. Mine reads 13.6 when running on a good known battery. Changed alt with no change. would like to see 14+. I would look for voltage drop in the harness before changing the alt. Start from the alt and work back. Alt's are not cheap, and a bear to change. I believe that the alt works the same as my 2009 RR (smart charge) unlike the days of old of wide out 14.6 always, they only supply what's needed based on battery status and draw. But maybe someone can confirm the smart charge operation on the x350. I need to do a complete harness check and parasitic draw check. I may have a short to ground, that is drawing a lot of amps.

 

This morning I went to connect a code scanner. I only have a generic one but I figured charging is such a basic function that it should pull up something. Of course it didn't. However, I started the car to get some live data. When I did I heard a whirling sound coming from the engine. The bolts started at 12.4 and all they did is drop.
I'm pretty sure the alternator is not charging at this point.

I called a jaguar specialist today just to get a number to see if it was worth it. When I told him I only had 12.4 volts he said that 13 something was normal in jaguars so your number might be right.

 

I took the car in to check the charging system and it came back that the regulator was bad. At least it wasn't the transmission.

 

Hi Mark,

You're right about intelligent charging on the X350. This excerpt from the Technical Introduction explains the charging strategy, which was designed specifically for calcium-silver technology batteries:


Cheers,

Don

 

I've had the same problem. I replaced the battery and it fixed a handful of things, though I have seen the gearbox fault twice since. The engine will shut off for a short period of time after that error, from my observations; first time I had called to get it towed, but the guy arrived and it started first time. 5 minutes usually does it.

As for what causes it, I am not sure. My code reader doesn't read the gearbox error. I have wondered about water getting into the circuit as this happened after rain.

If you find out please post back