Hi guys,

I'm in the USA, in NC.

I have a '96 Jaguar XJ6 with 150k miles. I bought it 2 months ago and it's been a great car so far. Bought new top of the line battery the day after I bought it. The check engine light came on a few weeks ago after it almost died at a stop light (I know that's a known issue, so I'm not worried about that and will have it fixed soon). The alarm has been randomly sounding, so I unhooked the battery overnight last night and it cranked up great today. Today I spent a good deal of time cleaning the inside of the car and had the radio on the entire time, maybe 2 hours. I then drove around 40 miles doing a few different things. While I was out, I turned the car off twice and both times when I attempted to restart, the engine didn't turn over at all, no clicking sound, turned the key but nothing happened at all, the instrument panel was lit up and engine fan, etc started, but nothing at all as far as cranking. I tried a few times and the engine finally turned over - it did this both times I started it. When I got home, I made sure the battery cables were clean and connected tightly - tried to start the car and same thing, except this time it never turned over. I took the battery back to the local auto parts store to return it, thinking it was bad, but when they checked it, it had 650 CCA and 12.75volts, the clerk said the battery is in perfect condition. Also something strange that just happened today was the central lock wouldn't work and the trunk release wouldn't work either. Sorry for typing so much, but wanted to include everything I could think of. I would be grateful for any help you guys may have.

 

There are several ground and hot connections in the Jags. You need to locate and clean all of them, most likely. The electrical diagrams are available in the sticky's at the top of the forum page.

 

Thanks RJ, I appreciate it.

I cleaned all of the neg/pos connections that I could see, it was 4 or 5 of them. I tried to start it again, but nothing happened. I kept trying to start it, turning the key to 'start' maybe 6 or 7 times until, surprisingly, it started right up. I drove it around the block and came back home. I turned it off and it started right back up the next three times I attempted to start it (within 10 min of driving). I let it sit for a few hours, and then the same issue, turned the key to start, then nothing. I kept turning the key to start, probably 10 times, and once again, it fired right up. Do you think this is a starter/solenoid issue? I'm not really a tech guy when it comes to car electronics, but I try to learn as much as I can. Thanks for any help you may have.

 

I probably should not respond because I have only had my XJ6 a couple of weeks and haven't looked at the electrical schematics yet. Nor did I locate the starter, for that matter.
That being said, I would try to determine if power is getting to the starter. I expect there is a connection on the starter to which you could connect a test light to ground and see if it lights up when you turn the key. I hope someone with more information will chime in.

 

The "could be" list is rather long. Poor connection, igntion switch problem, relay problem, etc

Next time this happens take a peek at the gearshift indicator. The "P" should be glowing red. If it isn't the starter will not engage and your neutral switch needs adjusting.

If that doesn't pan out then I suggest making some checks at the starter relay to determine if the problem is upstream or downstream of the relay. You'll need a meter or test light and, of course, you'll need to make the checks when the problem is actually occuring.

If you want to do this I can give you the wire colors and expected results

Cheers
DD

 

In a nutshell....

The ignition switch completes a ground path to energize the starter relay which in turn powers the starter solenoid to engage the starter.

The ground goes thru the "crank control" segment of the Body Processor Module and then thru the neutral switch before energizing the starter relay.

I'm not entirely clear on what functions the processor module performs relative to engine cranking but it communicates in some fashion with the engine ECU, the transmission decoder module, the security module......

Cheers
DD

 

Had intermittent starting problems for years on my XJ6. New batteries and a new starter didn't solve the problem. Finally discovered that the heavy (+) cable from the battery to the starter isn't a continuous piece of wire; there's a connection on the pass. side of the vehicle where the wire passes from inside the cabin thru the firewall into the engine compartment (look for a BRASS nut on the firewall). That connection was loose. Cleaned and tightened it and life got much better.

 

Thanks tsfo,

That's very helpful info, thanks for that. Is it easy to find? I've been looking at the electrical diagrams, but it might as well be written in Chinese.

 

I found the brass nut, was one on the drivers and passenger side, cleaned and tightened both of those. Unfortunately, it didn't help. I've cleaned all of the connections that I can find, I guess the mechanic will have to take it from here. Why do Jag's have so many grounds? Do most other cars have this many?

 

Yup! :-)


Cheers
DD

 

Earth cable from motor to chassis; accessible from underneath??
Try moving the gear lever, or starting it in neutral.

good luck

 

...finally got a chance to have car towed to my mechanic today.. should know soon what the issue is.

 

So, my car is still at the mechanic. It's not the starter. He took the starter apart and said it looked perfect. He has some machine that he can hook to the starter and it starts every time. He thinks it could be wiring between the ignition switch and gear shifter, is this common? I had no idea this was going to take so long...