Does anyone have a diagram and/or photo of how their alternator wiring is connected, particularly for a car with premium sound since the alternator includes the noise suppressor hookup?

I know it isn't rocket science, but after changing my alternator the new one quit charging soon after. It is probably just defective, and I simply swapped the wiring over from the original to new alternator, but wanted to double check before I install the warranty replacement.

One of the curious connections to me is the short jumper wire from the main charging post to a smaller post on the alternator back. I wonder what that is for?

.

 

My 96 without the premium sound system has the suppression module . To test the module it is a capacitor and you would read the climbing resistance as the meter charges it up . You can short it and watch it climb again . Where I worked if we had rockets there would be a giant smoking hole in the ground . My radio call sign was Ace so it was base to ace and ace to base as I would drive to the aircraft to straighten it out before flight .

Editing , haven't had my tea yet

 

Thanks, also can someone put a caliper on the alternator pulley so I can verify that the replacement alternator I'm receiving has the correctly sized diameter pulley fitted?

.

 

2.138 inch on the rib points inside of the larger outer belt retention rib . Garage is very cold , haven't slurred up my brain yet to complete wiring diagram . Rotational speed would not make a difference on the DC output but the belt tension would .

 

That was fast Thanks!

BTW, also found this which is helpful too:

https://www.jaguarforums.com/forum/x...04/#post698006


By saying "belt tension would" I assume you mean if the belt were slipping, if so wouldn't that influence the generator RPM (rotational speed) or were you referring to something else?

.

 

Slipping is related to the amount of electrical load demanded ( this increases rotational resistance ) and the physical grip of the belt . It would effect only the amount of power ( not the voltage ) the generator can produce up to the point of a non rotational pulley which would be 0 amps and 0 volts

 

There is a alternator part number change at VIN # 787953 from DBC6819 to LNA1800DA . All supercharged is LNA1800BA

Mine is 755xxx with the DBC6819 as marked

Still working

 

OK, I've now replaced my alternator with an Autozone Duralast Gold 13524N twice. This is a remanufactured unit, and so far it seems that remanufactured alternators are just about all that are available anymore. This one was about $150 which seems to be the typical price, unless you get one from a Jaguar vendor which is then $500-1200.

Both Autozone alternators failed within a few days, initially being somewhat more sensitive to RPM and especially low RPM idle than I would have expected showing the voltmeter swing a bit with RPM changes, then intermittently not charging, then finally failing to charge entirely.

In both cases the temperature was cold when it first didn't want to charge, 20-30F, and during the early failure stages of intermittent charging it would seem to start charging once warmed up. To be fair we've had a lot of cold temperatures, so this could be a coincidence?

I've still got the second one installed, but it is starting to charge intermittently, and failed to charge twice on me today. This was after driving it for a full day without issue over 100 miles. But based on past performance and what I'm seeing now, it will probably completely die like the first soon.

Normally I would attribute the first failure to being a poorly made remanufactured unit, but two in a row? It certainly is possible, but now I'm wondering if something else is wrong, although I can't imagine what it could be.

I've triple checked the wiring, and it's right, plus I don't think it would have a "slow fade" death if I'd miswired it, right? That would have been an immediate problem I'd think, and one almost can't wire it incorrectly anyway. The only connection one might confuse is the ground for the noise suppressor, the rest are either a modular plug or the big positive terminal.

The battery is brand new, replaced in concert with the first alternator.

Other than these Autozone alternators being junk perhaps, is there anything else related to the alternator that could be bad or failing I've not considered?

The rectifier and regulator is part of the alternators, so that's been changed twice.

The only other part attached to the alternator is the noise suppressor. Do you think that could be related in any way? I guess I could disconnect it and see what happens.

What does that three prong modular plug on the rear of the alternator connect to, and how is that related to maintaining the voltage? Could that be related to the problem?

I've cleaned all the connectors at the alternator and battery, and all are shiny clean.


Any other ideas?

I'm at a loss and am getting very tired of swapping out alternators in the cold, and need to get the car back on the road reliably as our "spare" car is also out of commission. I've never had so much trouble with an alternator in my life.... very frustrating.

Perhaps I just need to buy a "$500" alternator, but if so, at this point which one.

.

 

My apologies for not getting back with you on your wiring hook up confirmation .

I went through 3 battery chargers with them , they no longer carry the brand .

I should have a " new " voltage regulator by mail in a couple of days and will spin test it at the auto parts store and see if it is any good for I'm sure they are not quality controlled as the come out of the factory . Spun tested the alternator before and only the regulator part failed as I hooked up the battery backward in a period of frustration . The brushes are at 1/2 wear life and the diode rectifier tested good .

Have you checked fuse # 10 / 5 amp RH Engine fuse box ? This controls many other things and can be sucking down the regulator power source . You can disconnect some of these sub - systems and see if you get results .

The White / Blue wire in the round connector is the regulator power source wire labeled as IG

The Slate / White wire in the round connector is the monitor wire to the instrument cluster labeled as L

Terminal D is not used

The F and B+ terminal holes in the IN435 voltage regulator pic below are the brushes terminals

I wouldn't recommend disconnecting the suppressor as this smooths out the left over AC voltage after the rectifier diodes to be more pure DC . This dirty electricity with some AC in it could cause problems with many things to chase down and fix .

Did you notice any radio noise before and after the alternator change as this is the test for dirty electricity .

To test the suppressor is a 220000uf capacitor

Editing

 

Thanks, I'll do some additional checking this weekend once the snow has melted.

Has anyone else had this sort of alternator intermittent charging that would NOT be caused by a faulty alternator, and if so what else could cause it?

For example: "The White / Blue wire in the round connector is the regulator power source wire labeled as IG" ... could a wire break or faulty power from this cause this problem if the regulator wasn't getting power.

I'm just very suspicious that three alternators are bad and failed in the same way, original, replacement 1 and replacement 2.

.

 

Saw on a different topic where the round connector was not seated well and once seated well it was OK .

Saw where the sounder was internally shorting based on it's wet environment behind the open headlight design .

You can pull out the washer pumps relays as well as the A/C clutch relay .

There may be some corrosion going on in the connector , hard to see .

The connectors for the nozzle heaters are underneath the plastic
trough and would need to remove the wiper arm and probably break the plastic trough hold down screws

Or you can remove the fuse and once you determain the power socket put a meter on the other socket wires ends and massage and pull on that White / Blue wire to see if it " opens " . Best with a old school needle meter as the needle twerks . if you read the relay socket with everything installed you should read a open or infinite resistance to car ground

Autozone did say they have a high return rate on remanufactured alternators and for $10 more you can get a new off brand and a new Denso is $ 180 for the X300 with a lifetime warranty . They were surprised how much the price dropped .

 

Well it turns out that the Duralast Gold alternator I've been getting from Autozone is supposed to be "100% new" even though the store manager initially told me they are still remanufactured units. I'm not sure who to believe at this point, although the alternators did look new. I paid about $150 for the "new" Duralast Gold alternator, which is also why I'm incredulous about the "new-ness" and quality. But maybe it is.


Anyway, I plan to put a meter on the "IG" connector wire to see if it isn't getting power consistently perhaps by a dirty or loose connector, or maybe broken wire that is heat/cold sensitive, or as you suggest perhaps from one of the other siblings on that harness having a short or other issue.

Just to double-check, does the "IG" connection correspond to the "39" label on the diagrams above?

Would you agree that a poor connection and supply of power through the "IG" connection and thus intermittintly powering the regulator could cause these phantom "alternator not charging" symptoms?

.

 

Yes on the 39 . Unfortunately it is not a hard failure in the driveway but out on the road after time after things warm up . By then this is a mode of failure of a voltage regulator .

 

Thanks, so is "93/IG" the "exciter" wire, or just power to the regulator, or is it really one in the same?

Actually I think my failure mode, although inconsistent, is more tied to cold than heat. More often than not it seems to have the problem in the frigid cold.

.

 

Perhaps if you were to run the generator in the drive for say 10 minutes with little electrical load and you don't get a charge light . And a second run with things cooled down with a high electrical load of blower fans , headlights and such and you get the charge light in say 2 minutes would point to a bad regulator faulting as it warms up . This is on the basis of the regulators supplying the field windings of the alternator a higher excitation voltage hence a high current in the regulator causing more heat to the point of failure . The other devices tapped into the circuit through point 39 will have stayed the same between the 2 test .

Does the charge light go away after things have cooled down in your observations between one day ( or period of time ) to the next ?

 

39 the same as IG would be considered the supply to the regulator . The excitation voltage is after the regulator powering the field windings effecting the stator windings tied to your B+ final alternator output . The excitation voltage goes up and down depending on the electrical amperage of the car demanded .

 

Thanks for the confirmation, that is what I thought.

So, I see on the diagram you posted above that there seems to be a connector "P161-2" (is that what that indicates?) in the harness between the fuse panel and the generator(IG/39) and A/C clutch 12V supply. I think I need to find that connector as well and see if it is dirty.


I rarely get a charge (battery) light, although I have once or twice. In most cases I think the alternator is charging just enough not to light the battery idiot light.

The symptom is that the volt gauge falls well below 12V and then the car stumbles and dies, always at low RPM and usually when in gear, say at a stop sign idling while in gear and on the brake. In some cases I can take it out of gear and let the idle bump up 100-200 RPM and then it will charge.

When the second (first new Autozone) alternator failed, it just quit charging completely at any RPM one morning when I went out to start the car, but I only tested it once by trying to start and run the car (then I removed the alternator to return it) and that was when the car was very cold and had been sitting for a day or two. This was after noting that the second alternator was very sensitive to RPM changes according to the voltage gauge, and started to intermittently fall below 12V at lower RPM.

This is what is starting with this second Autozone alternator.


But if I do need a better regulator, at least those aren't terribly expensive.

The Jaguar part number for the X300 XJR alternator regulator is: JLM11144

As noted above the alternator part number for the X300 XJR is: LNA1800BA

 

The Papa Indy 61 connector is located below the washer fluid cap and is usually the black one .

With the car stalling it would point away from a indication problem through the Papa Indy 61 and you rave a real problem with the alternator or other .

Editing after breakfast after analyzing you last post

 

Agree, just making a list of all the related connections and dependent power supplies so I can check them all at once.

 

The ECU will fail someone mentioned below 11.5 volts so that can explain the engine stall

The tap into the A/C clutch is a low current ( suppose to be ) control pulling coil and not the high power half

So the voltmeter shows a true charging fault

Still waiting for my " new " regulator to come in the mail . $ 30 free shipping

Cleaning the Papa Indy 61 connector may get your charge light more reliable as it and the connector next to in have a common history of corrosion

second alternator was very sensitive to RPM changes according to the voltage gauge points to the regulator not adjusting