i have a 1997 jaguar xj6 3.2 sport and there is something up with it,
i first noticed the problem a month or 2 ago when the car was having dificulty starting, long story short i ended up boost starting the battery and she fired up no problem, the problem seemed to disapear from then on but a few days later it happend again and again and was happening more and more, i guessed i just had a dodgy battery and put another one on that i knew was fine, i drove the car again today for about 50 miles and suddenly the radio turned off, shortly after there was a tunnel when i went through i put my lights on and the engine slowed right down i flicked to full beam and the engine diped even more so i turned my lights off then about 5 minits later the power steering went down so i pulled over and as i stopped the engine cut out, the battery now doesnt have enough juice to fire her up. im now thinkin its got to be the alternator, if so i want to try to fix my alternator rather than buy another one as i live in spain and i know it will be a right pain in the *** gettin hold of one, iv found out about voltage regulators that supply current to the rotor field coil via the brushes and slip rings. It varies the current to control the alternator output. alternators today have the regulator inside them. Older vehicles had an external regulator. Some cars use the vehicle computer to control the alternator. does anyone know if my alternator has an internal regulator or not and does anyone agree with what iv said about the alternator being the problem,
thanks

 

George,

You are NEW, HA, welcome aboard, you will sort your car, trust me, and as a side line you will enjoy your stay here, it is always fun.

Your XJ6 is commonly known as an X300 model, and this area is for the "older" versions of the XJ6, so MAYBE, one of our moderators (friendly watchdogs) will transfer this post to the X300 area to maximise responses.

Your alternator sounds like a prime suspect. Although the batteries in these cars is CRITICAL to proper functioning of all things electrical and of modern era.

The X300 is a "juice hungry" machine, and a GOOD battery is mandatory.

I would get a NEW battery, ensure it is FULLY charged, if in doubt charge it overnight, fire up the engine, let it idle, and then with a digital volt meter measure the actual volts at the battery, it should be somewhere in the region of 14.2v, and if so, OK for now. Load it up, headlights or a/c or similar, and read that voltage again, engine running of course, it may drop, but should NOT go below about 13.5v. It may be OK unloaded, but the regulator may be failing when loaded.

If it passes the "loaded test" you may have solved your problem with the new battery.

A known good battery may have internal issues, that is why I suggested a NEW battery.

The alternator on these is a Nippon Denso, and is INTERNALLY regulated, and is NOT known to be a problem item. The drive belt on the other hand is an issue, and may be slipping.

The negative battery terminal is also a problem area, coz the thread inside the cable end has been known to strip due to some gorilla overtightening it, and that will reek havoc with the electrics on these cars.

I would NOT mess with this alternator, even though as you say in Spain it may be a pain to source one. They are fickle things at best, not like the old style Bosch/Lucas stuff. Look around at suppliers on here, or google the UK suppliers, you aint that far away, and a rebuilt tested alternator is a lot less stress than messing with something unknown.

Check the engine earth strap/s and make REAL sure they are connected and tight, and actually giving a good earth, easy to test with the ohms scale on the same digital meter.

 

Welcome aboard, George.

I'm usually one of the first to hollar "daid battree!" But this loss of PS functionality sure lends legs to a slipping drive-belt worsened by increasing load on alternator, doesn't it?

 

Oops!

That was hardly worth saying ONCE! Let alone twice....sorry.

 

Welcome aboard you are in for some very, very exciting times. To deternine if the alternator is bad, charge up your battery real good then start up the car and disconnect the positive cable, if the engine stops you have a bad alternator. If it does not stop you might have a short or a relay problem.

 

I would check the bulkhead electrical terminals also- the ones on the outer sides of the firewall where the big poer cables terminate. They are known to work loose and cause problems.

 

The tunnel you mention, was it the San Juan on the A7? Or are you in a different part of Spain, if so, where?
I had similar symptoms a few years back and it was the alternator. Only a test on its output can confirm its condition.
What does the dashboard battery condition indicator read? When I had my problem, the needle wavered about all over the place, dropping dangerously low at times.

 

no i was further down than that still on the a7 though, good guess.
my dashboard battery condition indicator does exacly that,
thanks for the info mate

 

il have a look mate, thanks.

 

thank you for the info mate , il take your advice onboard and get hold of a volt metre and check the charge, il let you know how i get on.

i can see this site is gna be wel handy, only posted this yesterday

 

i have noticed that as soon as you turn the ignition the engine fan starts up, i dont know if this is normal or is that maybe a sign?

 

Normal.

There were issues with blowing fuses or something like that, so a loop was placed in the wiring to bring the 2 fans on at low speed whenever the ignition is ON, and the high speed is still available by thermo switch, or a/c pressure switch. Not the smartest fix, but simple and CHEAP, and effective.

Providing the fans switch OFF when the igniton is OFF all is normal as designed/modified.

 

thanks alot mate. i did think it was normal but i just thought id check.