I drove my 1986 Daimler Double Six to a local car show this morning and I heard a constant whine from the front that I had not heard before. It drove OK and I won a trophy in the Modern class (there were 3 classes: Classic pre 1979, Modern post 1979, and Rat Rod) After the show it drove home fine too and at home I checked for the whine. With the engine off and the ignition on, there is a loud electric motor-like sound coming from the right front and the pitch of the sound gets lower when I step on the brake and then back higher with the brake released. It sounds like it is coming from behind the right front wheel and it is quite loud. It does not appear to be an electric cooling fan nor the climate system blower nor the alternator.
Is there any kind of electric motor associated with the brakes on a Jaguar V12 Series III? The pitch change might be because of the brake lights drain on the battery, but the battery seems Ok and is not weak. Any suggestions on what could cause this noise would be greatly appreciated.
EDIT: I saw an old discussion of headlamp wipers that popped up when I submitted this topic and when I wiggled the right headlamp wiper shaft I could feel some vibration and the sound changed so It may be the right headlamp wiper motor that is running. I did have the lights on and the windscreen wipers on briefly this morning so the right headlamp wiper motor may be stuck in the on position.
So…Now should I try to fix the headlamp wiper motor switch or just pull whatever fuse powers the motor? Guess I’ll have to pull the right front wheel to check it out.
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Have your headlamp wipers worked at any time, Phil - due to the exposed position they tend to fail…
These wipers are activated by a relay, which is switched ‘on’ by the windscreen washer switch if the headlamps are lit. There is no specific ‘headlamp washer switch’ - but there is a separate headlamp washer motor, which should run simultaneously with the motors.
Since there is nothing else that can cause ‘motor’ noise in the area - your diagnosis as to cause is likely right. The circuitry is complicated, and involves diodes - which may have failed, causing current feedback in some way…
However, both sides are operated in tandem, so theoretically both wiper motors should then run. In which case the viper blades should move, and washing active - though may not for a variety of reasons. One motor may have failed for one reason or another - causing a ‘one-sided’ noise…?
Restoring full function is likely to be complicated. Temporary disabling the set-up is likely called for to silence the motor - while you muse options or work on the problem. The best idea is to pull the relay - which may or may not bring silence, but disconnecting the motors might be as easy?
That said; the headlamp wipers are not essential as most roads are paved these days…?
Frank
xj6 85 Sov Europe (UK/NZ)
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The fuse serves other circuits, so it should not be pulled. The best idea is to
Kirbert
(Author of the Book, former owner of an '83 XJ-S H.E.)
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On the XJ-S forum, we are familiar with a “moaning” sound that the car sometimes makes, and it usually comes from the area you’re speaking of. It sounds kinda like a motor running. I personally believe it comes from the air purge piping across the top of the radiator. I do know that my suggested mod of installing a 5/8" flushing tee at a high point in the heater circuit and using it as a bleed port when filling the coolant circuit seems to make that moaning go away.
It also might be helpful to remove the banjo bolt at the top right of the radiator and elongating the cross holes to better align with the passage in the banjo collar.
Finally, we have come to a tentative agreement that the jiggle pin built into the fitting under the fill cap on the coolant bypass pipe is installed backwards as fitted by Jaguar. One fix is to yank the jiggle pin completely out and install a check valve in the line to the banjo bolt. Another fix is to just yank the jiggle pin and fuggetaboutit. The point of all this is that the pump trying to pull coolant backwards through that jiggle pin might be making the noise.
Thanks for the replies, guys. After a search in my books for a solution here’s what I found. The XJ6 wiring book in the green binder does not show headlight wash/wipe but my Uniparts Parts Catalog shows two relays on a bracket with a square one listed as wash/wipe Module DAC1996 and a round one listed as wash/wipe relay UKC2421 and also fan relay (red) DAC1028. There is a bracket with three relays at the center front of the engine bay with two square relays and one round red relay. I removed the middle square relay but the right wiper motor still ran with the ignition in position 1. Looking back in my notes, on 7/10/10 a reply from Jag-Lovers Gregory Andrachuk I realized I was looking at the wrong relays; Dr A said:
“Phil: the furthest relay to the right of the group of three should have a red diagonal stripe on it (the stripe often wears off). …On the left side of the rail the blue diode pack and the black cylindrical relay beside it are for the headlamp wash/wipe feature.
So I replaced the silver relay in the center bracket and removed the round black relay from the left hand bracket but the headlight wiper motor still ran with the ignition in position 1. I replace the round black relay and removed the blue “diode pack” and the headlight wipe motor still ran with the ignition in position 1. I did note that the right headlight wiper is at the bottom outside of the headlamp pointing sideways while the left wiper is at the inside side of that headlamp pointing up. Looking back at earlier photos, the wipers are both to the inside sides of their headlamps pointing up, so the right headlamp wiper motor is out of its at-rest position apparently causing the motor to keep running.
I discovered that the lead from the wiper motor goes through a grommet in the side of the bodywork to a 4 pin connector buried under the wiring that runs along the top of the bodywork beside the right wing. I disconnected the connector and the headlight wiper motor no longer runs; There must be a constant 12 Volt supply from fuse 11 to the wiper motor that is then controlled internally inside the motor to stop it at the upright rest position. Problem temporarily “solved” until I have time to remove that wiper arm and motor. If the left headlight wiper ever fails to turn off I hope I remember where to disconnect it.
Moral of the story – don’t drive in rain and if you have to, don’t use the windscreen washer with the lights on.
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It is indeed, Phil - it is to ensure that the headlamp wipers self park. And certainly, if the self/parking switches inside the motors fail to break current, the motor is constantly powered to run…
From the ‘parked’ position the motors are triggered to run by the headlamp wiper relay - but only if the headlamps are ‘on’ and the washer switch operated. Once triggered the motors run until washer switch is released - then they selfpark and stop.
With the ‘right’ wiper arm out of selfpark position the relay is bypassed, and has no effect on motors. However, the headlamp washer motor, colocated with the windscreen washer motor at the reservoir, is still controlled by the relay…
Have you tried removing the wiper arm/blade to see if the motor then runs stops as appropriate? Motor powered without moving the wiper arm implies that the arm slips on the axle - or the motor is blocked. Neither of which is good, but a locked up motor will eventually burn out…
Incidentally; does the other headlam wire work as is should…?
I had never known if the headlamp wipers worked since I did not fully understand what sequence operated them and seldom drove in the rain. On the way to the car show that morning I did encounter rain and did activate the windscreen washer with the lights on.
At home, with the constant motor sound happening, I flipped both wiper arms forward so they were not inhibited by wiper contact with the headlamp and the right one did not turn when that motor made the continuous sound so there must be something broken inside the motor, but the motor shaft does not turn freely either. I can confirm that the right wiper spray did work because of the watermarks on the right bumper cover when I arrived at the show. (I thought it was just road splash at the time.)
Out of curiosity, whenever the current rain abates, I’ll try having my wife push the windscreen washer button with the lights on while I observe from the front just to see if the left one wipes as it should; I was never curious enough before to check.
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Headlamp function is seldom checked specifically these days, Phil.
In the old days, with dirt roads, gradually loss of lighting gave a warning - with signs of malfunction clearly visible. Direct check is a ‘two man’ job…
There is a single pump serving both headlamps, but hoses may be individually clogged/detached/broken. Or a nozzle clogged…
