2000 XJ8 75,700 miles.
Have I proven my alternator is going bad & is the cause of these problems?

Last night made a 5 minute trip - normal operation. When I started the car for the 5 min drive home, I heard a high pitched whining noise at idle which increased/decreased with throttle. Checks; All fluid levels good, OBD-II Good (P1111 only), battery ~12.4 V before today’s 30 minute drive & 12.2 V just after (NOT a good sign, usually just after a drive it is higher.) Charging test @ 2500 RPM = 12.2 V red light Bad! (Normally charging tests 13.95-14.07 V)
I used a multimeter directly on the battery in the trunk but, for charging test, I used my cigarette socket plug in tester.

Also, starting along with the whining noise, I get ABS light icon amber & Amber color messages; Trac not available, ASC not available. I had occasionally had these messages in 2011-2012 & did the wheel speed sensor removal/cleaning w/o success & ended up having the ABS module rebuilt 2-2012 & that fixed the problem until now.

So, assuming it is the alternator whining & putting out insufficient voltage to run the electrical system & fully charge the battery, can this cause those ABS messages?

Regards,

Steve

 

I think you have it right. It is the alternator.

I just went through this 3 weeks ago and your symptoms are same as mine. Don't count on the battery idiot light coming on, mine never did. In fact, I did not even get any of the other messages you got until it was too late. I can tell you though, it is no fun being stopped dead in traffic waiting for a flatbed!

Replaced the alternator and all is well - didn't seem to hurt my battery either.

 

I believe you need to do a bit more sleuthing.

I always do the headlight test. Aim the headlights on a garage door and turn on the lights- then start to load the charging system, high beams, rear defrost, seats and wipers -- watch the headlights. A properly working alternator will keep up as you load the system. If the lights dim or get more then a tiny bit brighter with higher RPM's then the charging system is not working correctly.

Noise: The diode pac inside the alternator's regulator can make a whining noise when the alternator is trying to charge a bad/shorted battery. This happened last year on one of my MB's. I did the head light test and could not get the lights to dim - had the battery checked. Battery had a short. The alternator was basically stuck on max output.

It is not unusual for a failing alternator to take out the battery -- or weaken it to a point that it can't hold the volts. You still can't use the battery as an indicator. We all know what a weak battery will do to the electronics in the X308 .. setting off all kinds lights. Any drop in volts -- be it the battery or the whole electrical system under load can make the electronics go wacky. The engine itself actually requires very little electrical power -- and will run with low volts.

Normally, when a bearing goes (if that is your noise) the output of the alternator is not initially affected -- they just become louder. Most of the time when alternators fail it is the diodes in the regulator pac. I have had brushes go .. they can make a noise .. and normally you get a reduced alternator output -- that normally takes a lot of miles

You need to confirm the alternator output -- and check the battery. I have had very mixed results with rebuilt alternators. Normally the problem is the diodes -- I get a new regulator and fix the OE. With a bad bearing -- maybe you could find a local shop. Not many of them still around.

I wish I could be a bit more helpful on the particular Jaguar alternator. They have proven to be very reliable -- I have never replaced or fixed one. So I don't have ready information on parts.

 

I went through this back in August. Was driving heard a high pitched whining sound. Thought it was the belt driving around. Suddenly the Traction Control lights came on, then others started to follow. Barely made it to the side of the street. Did all the test to check the alt. People told me it might be other items. Apparently the alternator seemed to be too easy. I tested all the bulkhead connections all seemed good. Finally decided it was the alternator took it in had it rebuilt for about $140 w/3 year warr....
[B]Here's the thread from my time with the alternator.[Good luck./B]
https://www.jaguarforums.com/forum/x...rnator-125354/

 

Larney: Do you know what part failed? I'm wondering what would make the noise?

Always better to fix the OE's. I had nothing but trouble with the Bosch units years ago ... and was out of the country two years ago and my local guy replaced my other MB's with a $350.00 rebuild rather than fix the OE with a $80 part.

 

I did the headlight test. With my Voltage/charging tester plugged into the cigar lighter. I did not race the engine to 2500RPM. Turned on high beams, stereo, rear window defroster, fan. I saw no change in headlight brightness! It was dark in the closed garage. I did see a small drop in Voltage on my tester.

BTW, if the alternator was easy to remove, I’d try to DIY. Probably with a rebuilt one. Or maybe find a shop to rebuild mine. Many people have posted here & elsewhere about spending many hours trying to remove the alternator & making special tools to do the job. Sounds like a nightmare for me. Much harder than replacing an ignition coil <GRIN>
I looked up the cost of an alternator on Gaudin Jaguar, $808.55 MSRP, $707.48 Online. YIKES! I call an independent shop, $550 for a rebuilt Jaguar Alternator + $155 labor. I will now call Jaguar, I expect they do not use rebuilt alternators & will quote me close to MSRP + higher labor so, probably >$1,000!

I wonder how long I can delay this? I think I may get stranded so, have not driven anywhere since yesterday & probably should only drive it to the repair shop.

 

Put your positive lead on the false bulkhead, and the negative lead on the throttle body, and see what the voltage is. That is what your alternator is producing.

I'd suspect the alternator, too, but if you want to be sure, swap the battery with one from anther car.

Go through the Electrical presentation in my signature if you want more info on the charging system.

 

I also went through the same situation 2 months ago found out was the bad alternator and i also changed the battery

 

<<<@!1!@>>>
Thanks, I had read your Electrical PDF b4, Nice of you to post that.
I looked & can easily access the TB but cannot reach the wall @ the back of the engine compartment w/o removing the plastic shelf. While my Cigar lighter tester is not as accurate as using a multimeter directly, the fact that it dropped fron 14+ V to 12.2 V is significant. As is that whining noise.
This is the same exact noise mine makes! I found a video.

My Interstate Battery is 2 years old. I really doubt it is the battery & the battery could not cause that sudden onset whining noise. I heard back from Jaguar & unfortunately I was right. $1,300! $962.17 (Higher than MSRP!)for the new alternator & 1.5 hrs. Labor $225.00 + ~ $100+ of misc fees.

The good news is They can fix it Tomorrow but, the independent shop can only “maybe” squeeze me in Friday for the rebuilt alternator for $675-700. Never used them b4. Jaguar says they do not recommend rebuilt alternators (what a surprise) They sometimes have them but do not have any now. When they do have one they only charge ~ $50 less that a new one. If I bring in my own rebuilt alternator Jaguar will put it in but cannot warranty it. So if it fails under warranty they will have to charge to remove replace. Tempting to buy the Gaudin Jaguar new one online for $707.48 & bring THAT in to Jaguar here. But, I’d have to wait for it to arrive & have only the one car.

 

When you test a alternator it is somewhat like testing a battery -- a load is introduced and the alternator output is watched. Depending on the regulator the output is not liner ... the battery is actually a stabilizing force.

A bad battery can cause a alternator to make noise .. not common -- but I have had it happen. Normally when the regulator fails -- the output goes to 0 and the battery is drained very quickly. A bad bearing will just get louder until it fails -- but the alternator will still produce. The brushes going will often cause a noise and strange output.

You don't need a a new Jaguar Alternator at $800+... and I would never pay $550.00 for a rebuilt one .. especially without knowing exactly who did it and what was done.

Frankly for the low cost of the independent R&R -- I would try and get a Denso rebuild for $200.00. It's a shame you don't have another car .. with the low failure rate .. I would even consider a used one for $65.

 

I hope my 2 year old Interstate Battery went bad & caused all these problems including the whining noise but, that would be too good to be true. Sounds as if you think rebuilt alternators are every bit as good & reliable & long lasting as OEM new ones. Maybe you’re right if a reputable company does the rebuilding. I’m not willing to chance the DIY R/R & no shop will warranty the installation an alternator that I did not purchase from them.

I searched & found for 2000 XJ8:
Denso Remanufactured Alternator
SKU: #210-0421
ITEM: #DEN210-0421
$234.88
Denso - Search Results: 210-0421

Also got a list of local Auto Parts stores from the Denso Website.
If I had another car & wanted to undertake the DIY R/R, this would be a viable option.

 

I followed the directions from some one on this site. I took the alternator out of the side wheel well. Took me about an hour to get it out and about 30 minutes to get it in. No special tools required.....

 

Here's the directions I used for my 2000 XJ8. They were spot on.

Join Date: Dec 2012
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Default Very easy to remove do it in 20 mins or less
I have a 2001 xj8 the easy way to do it with out removing all that stuff is to
1 disconnect the battery
2 disconnect the air filter cabin not completely but just enough to get it to set to the the driver side of the engine
3 loosen your tires on the front passenger side and jack up your car remove that tire take off or loosen the splash guard in that wheel well i just loosened it
4 Go to the top under the hood loosen the tension-er so you can get the belt off of your alternator off to do this when you loosen the bold hold it with a pry bar when it loose take the belt off and release the tension-er slowly
there are two screws that hold the alternator on the bracket take those out from the top under the hood one is below on the bottom of the alternator which you will have to get under the car and the other is on top on the side where you had removed your air filter cabin there is a NUT IN THE BACK WHICH YOU HAVE TO HOLD ON THE SCREW ON THE TOP WHICH IN BACK OF THE ALTERNATOR
5 some people may have a splash guard in the undercarriage remove that
6 wiggle your alternator and it shall come some what free
7 go back to under the hood and reposition your alternator and take the positive boot off the harness and remove the nut and remove the wire from the alternator
6 from under the hood of the car again take the clip that was next to the nut you just removed off the alternator with a pair of pliers be sure not to squeeze to hard you may break the clip this will take off the second harness

7 take the altoneater though the body of f the car and slide it though the lining of the wheel well

Repeat backwards to reinstall
WARNING DON'T KNOCK YOUR SELF OUT TRYING TO REMOVE THE AIR FILTER CABIN IT WILL SPLIT YOUR WIG IF YOU TUG ON IT IT A RUBBER BOOT CUZ I SURE DID LOL GOOD LUCK!
These were spot on...
Thanks for ALL the input and advice. Sure makes the job easier...
__________________

 

I don't just replace parts .. Checking the alternator and the battery is quick and cheap with the correct equipment.

Normally, a failed alternator leaves the car dead. The alternator fails to provide enough current ... the battery starts to drain .. the car dies when the battery can no longer provide the volts to run the engine. It does not take a long time .. and since the battery is dead .. the car will not crank. From your description, your car was able to drive and be restarted. I was giving some possibilities since it did not sound that the alternator had died. It could be weak??

Nothing wrong with a quality rebuilt part ... but if you read my previous post you will see that I mentioned that finding a quality part can be difficult. Lots of remanufactured starters and alternators are junk. We had a lot of problems years ago and stopped getting them from the local parts stores .. and I hear this is still the case.

I like to rebuild the one in the car -- The vast majority of the ones that die need a new regulator. The alternator is really not even touched -- couple of bolts and the old one is off the back of the alternator and the new one is in place. Having a bearing go is a different story .. or the brushes .. that requires dismantling.. I take them to a shop.

I happened to remember that I had ordered a Denso unit for an 07 Lexus .. I ordered it online .. it was a Denso alternator remanufactured by Denso (authorized) and it came in a Denso box. The link you have is not Denso -- this is the problem. The unit in the car is by all accounts a Denso alternator -- so any proper one is going to be a Denso ... it does not equate that Denso did the rebuilding.. Lost of these have Chinese parts. So you get a lifetime warranty .. and it dies in 6 months and pay the labor again.

I would try and find a quality part and get it installed if your local independent can't or will not have the original rebuilt .. My local guy will have them sent out and rebuilt.

 

When you read the fine print -- remanufactured parts are mostly "checked" -- so they only replace what needs to be replaced ... a remanufactured unit will not necessarily have new bearing ......as an example.

The link provided goes to a site that says they are an authorized rebuilder for Denso -- the part is $149.00 plus core of $34.00 .. + shipping both ways .. so the core will cost $12.00 to ship back. I would give them a call or another authorized rebuilder. It also says 1998 -2000 .. so Jaguar may have used more then one.

Denso® 210-0421 - Jaguar XJ-Type 1998-2000 Remanufactured Alternator

 

Larney, congratulations on your 90 minute repair! You saved a lot of money. Where did you get the replacement alternator? I had seen those same instructions posted but, I had also seen multiple posts where people had much trouble & one where a guy posted a photo of a special tool he “made.” I also recall one where it was recommended to remove an engine mount. Maybe the instructions you reposted are the best easiest way to do the job.

Yeldogt, I’m not planning on just having a mechanic replace the alternator. Of course, they will test first to be sure. I think your suggestions are good ones. If I could have the car out of service for a week, I would probably chance removing the alternator myself, send/take out somewhere to rebuild it or maybe buy a Denso one from the link you provided. I am not a mechanic. I have done some repairs though. Usually it takes much longer than I had planned. Leaning curve, Murphy’s law, etc.

Regards,

Steve

 

Sadly, the vast majority of repair facilities simply replace parts ... and more often then not they use the cheapest parts available .. even when better parts are not much more.

Quality remanufactured parts are available ... The alternator in the Jaguar is nothing special other than it being a good unit from a quality manufacturer.

I understand your situation -- wanted to give some information so you did not end up with a unneeded $800.00 bill.

 

I had mine rebuilt at a local place. Cost $140 w/3 year warranty. Looked them up read the reviews. Happened to have a friend who had an alternator rebuilt there. The shop was dirty but he rebuilt it in about 6 hours. Also I'm hardly an expert mechanic. But it did end up being easier than what I expected.

 

A few years back I replaced the brushes on the alternator at 150k miles. they were 3/4 worn.
I got a good quality set ($30?) and would not hesitate to do it again.
There are plenty of YouTube videos showing how to do it with basic knowledge and tools.

 

Larney, you did very well! $140 + your 1.5 hours labor, outstanding.


I had it replaced @ Jaguar Wed. Well under 2 hours. Cat purring again! Still overpaid by a huge amount compared to a rebuilt alternator & DIY repair. (New Jaguar Alternator must have body made of platinum & gold rather than aluminum!) Makes me seriously consider buying a 2nd car to be able to take time with learning DIY repairs such as this one & if run into issues (And I probably will) I will still have a car to get around! I just had too much important stuff to do Th, F & all next week to chance it & renting a car destroys a lot of the savings.

Jaguar quoted $1,300 but, with coupons/discounts “probably” ~ $1125. I just was not comfortable trying that independent shop for a rebuilt one after all my troubles with the last independent ship I had used in 2009. (Probably not fair to independent shops) I was able to negotiate the price & ended up getting it for $946 incl tax. They agreed to price match Gaudin Jaguar ($707) & then got discounts on labor.

Then an interesting thing happened. My service writer (a very nice & honest guy that I’ve known several years), says the tech said they had to jump-start the car bc the battery is kaput! (MSRP ~ $200+ ) He asked if I want a new battery. I said I use Interstate battery (Interstate MTP-93 850 CCA )which they sell for less than Jaguar brand & it is a 85 month battery & it was installed 2 years ago (somewhere else). If I did need a new one, Interstate should adjust it & I have paperwork & last time they just scanned bar code on battery. I also asked if a load test was performed. He called the tech & no test of any kind was performed on my battery! Tech says since battery is flat would need to charge at least 3 hours b4 load test (true, cannot load test a flat battery or it fails regardless of being bad or merely discharged). I was not going to wait 3 more hours! I said jump start it & I’ll get in & drive it 20 min on freeway & then test it myself. I drove 25 min @ 70 MPH then home & tested with multimeter & it put out 12.78 Volts! YES! My battery is just fine. (Note, had the battery not fully charged my plan was to trickle charge it overnight & watch it carefully, & if started discharging, take it to the place where I last had this Interstate put in (after calling to verify they have new one in stock) & have it adjusted once again at a far lower price than Jaguar charges.)

Bad news is while waiting, I saw the Range Rover Evoque & I think I want one. <GRIN>

Regards,

Steve