Hello Everyone,

I am new to the Jaguar family and new to this forum. I was gifted a beautiful baby blue 2005 X-Type Jag from the family with 127,000 miles on it. Mostly everything is original with the exception of wear and tear, tires, brakes etc. I took the car into a Jaguar dealership to get a read on why the battery light was coming on if the battery was good. They performed an electrical diagnosis, stated the altinator needed to be replaced, along with coils and spark plugs. Due to cost, I took the car to a chain store to replace the altinator. They confirmed the battery was good. However the batter light came on again about 10 days later. I then took the car to a euorpean car mechanic, battery was trash, swapped it out. No more battery light issue, which brings me to the title of this thread. After driving for short to long distances, when I return to the car, it will not start. Dashboard lights up, you can barely hear the car trying to crank - If I wait fro 20 minutes to an hour - vroom! She starts. Any ideas? Starter fuse was checked.

Thanks in advance - apologies for the full story but felt some background was needed.
Have a good day all!

JagDee

 

Hi JagDee,

Firstly, welcome to the forum.
Secondly, I see in your profile you have a 2005 vehicle, what engine size and is it automatic or manual transmission?
It is a good idea to list your manufacture date, saloon /wagon, engine size and transmission type in your signature so anyone reading your questions in the future can start referencing the right data for you.

Can you please elaborate a bit on the actual starter activity when it is "not starting".
Do you hear the starter engaging and is it trying to crank the engine over, but just doing it very weakly?
Or are you not getting anything from the starter at all when you roll the ignition key to start position?

If you are getting a starter response (albeit weak) then it could be bad battery cables from the battery to the starter terminals.
X-Types do get an issue of failing high current cables either in the positive feed to the starter or in the earth returns. They can look OK, but get very hot where the cable might be corroded under the plastic insulation.

If you are not getting any starter response at all when car is hot, then the hunt will begin for a cause. There are a lot of safety systems that can inhibit the starter from being commanded to engage.

So let's see what else you can tell us about your beauty's symptoms and hopefully we can help.

 

Well, the issue can be something simpler, and very common on these cars: the battery cables, yes, the cables, corrode from the inside - unseen. Clearly, if the cables are bad you will have problems with charging the battery, and even if the battery IS charged, with starting the engine. The first symptom I had of this issue was indeed the battery light coming on. Replacing the + cable solved the problem - no further issues.
The test: with draw on the battery (ideally with the engine running...but in this case that may be difficult) - turn on headlamps and climate control - After a few minutes hold your hand in turn above (not touching) the negative and positive terminals of the battery; if they both are at ambient temperature, then the cables are not likely to be the problem. If one of them is hot, significantly hotter than the other, then you have found the problem. Replace the hot cable. Problem solved.
It is amazing that mechanics are willing to ignore the simplest and most obvious causes of problems.

 

JagDee, like both posts above talk about, your issue is most likely a bad battery cable (probably didn't have to replace the alternator as these rarely fail on this car). I will expound on what SOV said. I would say to start with letting the car sit over night (get everything as cold as possible). Now, start the car and turn on the following things:

-seat heaters
-rear defrost
-dash fan on high
-headlights

Now, let the car idle for 5ish minutes. With the car still running, open the hood/bonnet and cup your hand OVER!!!!!! the battery terminal. Do they feel the same temp as the surrounding metal or is one/both of the terminals much hotter (if you have an IR thermometer, you can check both terminals and they should be within 5 degrees of each other). If one is hotter, then replace that cable. You can buy the Jaguar cable, but that will be a lot more expensive. You can normally pull off the cable in question, go to your local auto parts store and they can match up a cable for you. Install the new cable and see how things go from there.

One thing I will add to the things to check. When looking at the connections, all should be a silvery color. If you are seeing say a light green/gray corrosion or the connection looks dark, a wire brush should be taken to the terminal and the lug on the cable to get them back to a silvery color. Even something as simple as a 0.2 ohm resistance (smaller than what most home multimeters can accurately read) is enough to completely wipe a voltage from a wire. For example, the electrical load I mentioned you to have on the car will be pulling about 80 amps. Even with a 0.1 ohm extra resistance in a cable, that will result in an 8 VDC drop. So, while the battery is outputting 12.6 VDC, the far side of that "high resistance" is only seeing about 4.6 VDC. Obviously, most things in the car will not work with a low voltage like that. You don't see it normally with the car running as the ECU will see this lowering voltage and crank up the output of the alternator to account for this. hence why as you are driving, all seems normal, but when you turn it off, you have issues (ie, the battery is a fixed voltage, so, it can't raise itself to account for the extra voltage drop).

 

Hello Mark,

Apologies for the delayed response. This is a 2005 3.0 AWD, automatic, but you can switch to manual (1-4 and shift). I am unsure of manufacturer date.

You can "barerly" hear the car whine to try to turnover. The hood needs to be up, ear close to the engine.
"Positive Cable" was checked im told. Relays checked.

I can say my driving conditions range from 35 -70 mph, radio and AC always on. After around an hour of on/off stops. Issue appears. First time after sitting while grocery shopping - 20 minutes. Twice after 2 minute stops. - Same day.

I do appreciate the help and notes that I can pass to my mechanic who is trying to make the car fail live, before offering a solution. So far, no cost to me, just time and patience.

Thanks Again,
JagDee

 

Thank you Gregory, I will pass along to my mechanic and see what he says.

Kind Regards
JagDee

 

Hello Chris,

Thank you for the details. My guy said the cable was good, but you never know! I will give that a shot as well and keep everyone posted. She just will not fail, while he is troubleshooting it, so he is going only on my description of the problem.

Kind Regards,
JagDee

 

Hi JagDee,

While your mechanic is checking things, get a voltage reading of the battery when at rest state...should be around 12.8 volts.
When the engine is first started the alternator is told to apply a higher initial recovery voltage to the battery (around 15.2 volts) for about 5 minutes to quickly replace the battery energy used in cranking the car over.
Then the alternator is told to relax a bit and the output voltage to the battery drops down to around 13.2 to 13.5 volts as a general maintenance charging cycle is delivered.

With your frequent short runs, I am wondering if the battery is either not receiving the initial higher charging boost from the alternator to assist with rapid recovery, or the battery itself is being offered it but is not in great condition to absorb it properly
It is a simple volt meter test to take some "at rest" voltage readings (engine cold - when you know it seems to start OK) versus engine hot after short run sequence (when you tend to get the behaviour occur).
Then check charging voltage applied to battery while engine is running; immediately after the engine is started, versus a few minutes later when the ECM decides the alternator high charge mode can be relaxed.

You mentioned the alternator has been replaced, do you know if they fitted a generic alternator or a Jag x-type compatible one.
Some generic ones may not charge properly as the charging command from the Jag ECM may not trigger the third party alternator to respond properly.
The charging voltage tests should identify if the alternator fitted is not responding as intended.
Some of the other members here on the Forum can probably confirm what alternators have been successfully used as substitutes there.
Also you might like to search for other threads in this forum that discuss replacement alternators, trials and tribulations.

 

I will be the 3rd to recommend the test that Gregory and Chris mentioned above. A mechanic will test a battery cable by looking at it and seeing it looks fine and the connections are solid. That doesn't capture how these Jag cables fail. They fail (at least mine did) by internal corrosion causing decreased area for the electricity to want to flow which in turn causes higher current density. Pushing more current through a smaller area causes heat. More heat causes more resistance to flow of current. The car can fail when something wanting a lot of current like the starter tries to pull current from the battery when the cable is very hot. I do mean hot, when you do Gregory/Chris's test use a non-contact thermometer or put your hands near but not on the battery terminal to feel for heat. Could explain why your mechanic doesn't see the problem, he pulls it into his shop after it has been sitting and not when it is warm.

Also as Mark mentioned above Jag uses 3 stage charging, not all replacement alternators play well with that so if the problem onset is near when you installed a new alternator I would have your mechanic double check the brand & model of alternator he put in.

 

We have an update! The car finally would not start for my mechanic this morning. Noted issue: Ignition clylendar has gotten worn out and the key will sometimes not catch. Also noted, the key was able to "slide" with the engine running. I will send an update out once I have her back!

 

Hello Members,

Final resolution: When starting the car, the park gear was not engaged, (lit up red). If you moved from Park to Drive and back to park, it would catch and the car would start. Cylinodes were replaced. No issues since November. I will come back and post the details for the next person!