200 Tdi 90. The near-side side light fuse has recently begun blowing. I change it and the lights are OK until again. When I arrive the fuse has blown again. I have visually checked the wiring, pulled it all about and shaken the vehicle but cannot reproduce the fault while stationary. This is going to be one of those nightmare faults, any suggestions where to look? I imagine the final soution is to rewire the offending circuit. Cheers, Peter
Just a wild suggestion - I had a car with an alternator overcharging and it blew quite a few globes, maybe one or two more often than the rest. The big hint was brightening of the headlights at times.
Thanks for all advice, EMB, I've had a good fiddle with the socker but can't find anything untoward. Oily, I've inspected all the light fittings and refitted them, the front one is pretty crappy but doesn't seem to affect anything when I pull the wiring about. I don't think it is the brake lights as they are on a separate circuit. Jg, It is only the one fuse that keeps blowing so I believe it is something to do with that circuit, and I dream of the lights brightening!!! Skinty, I am looking at that dodgy front light fitting again, but as said, don't think it involves the brakes.
I've tried every permutation while stationary to replicate the fault: Swithing different lights on and off, turning the steering lock to lock, applying the brakes, putting her into reverse, turning on the rear fog light etc. etc. The fuse seems to blow at random when on the move sometimes it lasts for a couple of days (i've been running with the lights on during the day as a test) and then it goes again, usually at night! It started happening a couple of weeks ago and had never been a problem before. The fault must be after the fuse holder otherwise it wouldn't blow, I am surprised that so much wiring is unprotected before the fuse! If I can get to the back of the appropropriate fuse I should be able to renew the wiring. Then if it still blows I'll "know" it's a light fitting. What a bugger!
Did a rover 800 that kept blowing its ignition fuse at random intervals. Put a headlight bulb in the fuse holder instead of the fuse and told him to keep an eye on it (bright bulb means short circuit) but he kept it like that till he sold it ages later and never had another problem with it :)
I had a very intermittent fuse blowing time with a P38 RR. Three or four times a year it would blow the fuse supplying the brake lights when the brake pedal was pressed but this fuse also supplied the climate control (HEVAC), ABS ECU and some of the dash indicator lamps. Sometimes the replacement would blow straight away, sometimes it would be OK. It would always stop blowing as soon as I started to try and trace what was causing it. It seemed to happen more in the summer so I thought maybe summat connected with the climate control. Eventually I systematically spliced some in-line fuses of a lower rating in each of the splits to the different circuits. Next time the problem happened I had isolated it to the brake lights, turned out it was the wire feeding the high level lights in the tailgate was crushed under the tailgate trim near a fixing screw. It was worse in summer purely because of the tailgate materials getting hot and expanding when the vehicle was left in the sun.
Tony, I've been working up in fuse sizes and so far have reached 20 amps and still blowing. Jon, had to sit in a darkened room for a few minutes to get used to your idea, I'm going to give it a try as if nothing else it will tell me exactly when the short circtuit occurs. Thanks everyone, Peter
As you say it's a 90 then it should have a diagram of the fuses and what they are for on the back of the plastic cover. What circuit/s does this particular fuse run? If you can tell us that then we may be able to give you an idea what is wrong and how to test for a fault.
I have a 1996 workshop manual brilliant - only a circuit diagram for the alarm system!
At that vintage which'll be 300Tdi, I guess and therefore later than yours, the side lights are fused separately LH and RH with nothing else on the circuits. The number plate light will be on one side or the other
- don't know which.
I also have a very early 90 circuit diagran which may be 200 Tdi. This again has the LH and RH side/tail lights on separate fuses by side. The number plate light is in the LH circuit. There appears to be one connector in the line out of the fuse box (where front and rear are spilt off) other than the connectors immediately before the light units themselves.
If you can find this connector quickly you'll be able to isolate the problem to the front or rear part of the circuit.
If you can't quickly find this connector I'd start by dismounting the three lights units (or two if you've worked out that it's the RH side without the number plate light) and visually checking for obvious short circuits there. Then work 'backwards' following the harness looking for rubbing damage until it becomes too difficult to check easily. If you've found nothing damaged by that point you should have located the afore-mentioned connector. Open it up there and see what you find in the three legs separately.
If the OP wants a copy of that circuit diagram drop me an e-mail to my address with the obvious change.
As EMB suggested earlier if there's a trailer socket - particularly of the ripped off, dangly variety or if only the wiring remains - that's the prime suspect. Check it first.
Could the onset of this be related to the wet weather?
Just recently my 90 has been blowing fuses in the indicator circuit. It's taken a lot of searching and stripping down of the indicator switch which has improved it's mechanical functionabilty a lot - but alas not cured the fuse blowing. Upon suggestion of my local Landy mech, I checked out the hazard warning switch - couldn't find anything wrong. Had all the lights out and checked for shorting, earthing etc.
The fault is not consistent, but started immediately after a journey through a particularly heavy downpour. Operation of the left indicator would sometimes blow the fuse immediately, sometimes only after several operations. Operation of the hazard warning switch would blow two fuses at once!
Anyway, long story short:
I have now found the cause, and it is a badly sealed connection in the wiring to the nearside rear lights. Upon opening it up, it is very wet and corroded around the wires. Separating and drying the wires has cured the fault, next job is to clean, re-connect and seal properly the connectors.
So, in your case, take a look along the top of the rear cross-member, for a section of wiring loom going to the rear nearside lights - you might get lucky and find your cause there.
I know it's the left side lights and fuse. Trouble is it's intermittent. The fuse blows and I fit a new one and it's OK. Then it blows again after an unspecified period. The trailer socket is on a different circuit, so I know it's not that. I've traced right through and been unable to replicate the fault. What I have done now, is cut into the circuit under the bonnet and behind each light, then rewired between with a complete new circuit and so far it hasn't blown again. The Haynes manual wiring diagram seems to be accurate but if it is I am surprised how much wiring isn't protected by fuses - the instrument lighting for example. Thanks everyone, if it blows again I'll report back Peter
Em! The trailer tail lights pick up off the vehicle circuits(unless you have something really unusual and probably not standard). Anything from the pickup points back to the socket is suspect. Think again?
Dougal, You may well be right. But I can definitely say that they are not in the new circuit! However, this gives me another idea. I'll plug the trailer light board in and keep it in the back and see if that blows. It will certainly help to narrow things down further. Cheers, Peter
So far so good. It's been a week and the new circuit hasn't blown. I checked the lighting socket last night and everything was working even though I have bypassed the normal lighting circuit. So in this case it is on a different circuit as I thought. It may not be correct, but that's how it is! Thanks again to everyone who chipped in! Peter
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