I recently bought a 2004 XJ8 from an auction. The vehicle was damaged and sat with a dead battery for weeks, maybe even months. When it arrived I installed a freshly charged battery and tried to start her up. When I held the key in the start position the car would click approx every second over and over. It sounded like the starter engaged for a split second every time. I checked the connections and tried again with the same results. I gave up for the day. The next day it started right up. I've been driving it for the last 2 weeks with not one problem. Today I disconnected the battery to make some repairs and now it's not starting, giving me the same weird clicking. Anyone experience this before? It's not the battery, I load tested it.

 

Sorry for this annoying suggestion, are you sure it's the right size battery for the car? If it is too small and has not enough power it sounds like it would do this. I tried another brand new battery for a volvo diesel on my jag also did the same thing, I needed a much bigger battery.

Failing that it sounds like an alternator issue.

 

Yeah, it's a full size Jaguar battery that I load tested. I just tried it again and it's doing the same thing.

 

This car was lightly tapped in the rear, I had to change the rear fuse box. When this happened before it started the next day and I'am just wondering if there is some sort of timer that starts after you disconnect and reconnect the battery. Or if there is something I need to do after connecting the battery to get it to start again.

 

I had similar symptoms on a V8 AC Cobra, I know a completely different car but at first it was the alternator that was giving trouble, it was underpowered (in your case it maybe failing) so you could drive around but when you stopped the car and parked up it wouldn't turn on again the next day.

Later the starter motor failed to engage with what sounded like engaging then clicking.

The sound of the two symptoms were different, in the first case just clicking, in the second engaging then clicking.

-Is the battery on full power? Check it or charge it. If it's empty could be an alternator issue. If you do need to charge the battery, once you have your car started again you can run a check with a voltmeter to check if you alternator is charging.

-If thats all ok, and the clicking sounds like the starter is engaging at the start but then clicking, it could be a starter motor issue, mine was disengaging on the Cobra.

I don't know these cars or modern Jags at all so that's all I can help you with really, sorry.

 

The battery and connections are good. What is strange is the clicking, it's really more like a pulsing that is continuous and about every second when I hold the key in the start position. I know it's not the battery. It does the same thing if I connect the jump box with 200a boost. And I load tested the battery.

 

Hi Paul,
Tested battery and connections, ok. Replaced rear fuse board, ok.

There should be a small black box in the spare well with 2 fuses, check those connections. Also check the grounds around the car.

Whilst the car is shutdown, check the current drain on the battery to see if you may have a parasitic drain.

Check the gear selector is fully in the park park position or try starting from the neutral position.

Are there any warning messages when you try to start the car?

Just a few thoughts, hope it helps,

 

I have several batteries that check out but I guess the amperage was only high enough on one after I charged them all. It's frustrating, any one of these batteries would work on most vehicle types. This may sound crazy but I think the XJ senses the condition of the battery and only allows it to start the car if the voltage or amperage is at a certain level. I hooked up a 200a booster to it and it still would not start.

 

You need a battery of nominal power (95 Ah, 850 Amps) in fully charged condition, able to withstand 12.8 V and to deliver 500 Amps without voltage drop to be sure it doesn't come from the battery. The V8 is very greedy and the electronic systems don't like failing voltages, not like in other cars. A 200 Amps booster will not make it. Ensure first your battery is not the culprit.

 

Paul, sounds to me like you may need to change the starter.

You will be aware that it is a motor and a great big solenoid

which only closes intermittently.

Two bolts holding it on,one bolt not easy to get to.