Dash Light Fuse keeps blowing

[craigiow]

Hi, new to the site,

Just bought a M reg 300 TDI,

one small problem the car has and not sure where to start, ignition lights fuse keeps blowing, so hae nbo glow plug or ignition lights until i change fuse, but blows again after a short while,

also have no speedo or rev guage is this to do with same fuse ?

aparently new owner has had the problem since head was replaced could anything around there cause a short ?

[Evilgoat]

Glow plug shorting or bad?

I dont know the wiring well enough to say anything. No tacho would probobly be the same thing. guess a wire has been damaged someplace.

[Range Rover Blues]

Alternator, rev counter, fuel and temp guages plus a few other things.  You need to take the head back ouot and look for a trapped wire by the sounds of it then.

[craigiow]

cheers for the replies will get under the bonnet tomorrow and have a look round the head

[Evilgoat]

is she drivable?

[craigiow]

yeah drives perfectly just dash lights of,if i put fuse in even lasts a short while sometimes,

[Range Rover Blues]

That could well be a loose wire that's chaffed through the insulation.

[craigiow]

hope its that easy a prob. just a case of finding it now, strange bit is fuel gauge seems to work  well hope it is or gonna run out as says i have 1/4 tank  :(   

thinks this is of only thing it needs for mot so need to get sorted asap

[Evilgoat]

That could well be a loose wire that's chaffed through the insulation.

Sounds about right. trying to think long and hard about which instruments etc would be supplying a +ve feed to a sensor... I reckon the head change may be a red herring you know.

[craigiow]

only thing i could think of is glow plug leads as they must send some signal to glow plug light on dash ?

[Evilgoat]

Depends, without looking at the diagram I dont know. Its possible that it switches a feed from the dash, you could POSSIBLY test this by pulling the glow plug realy out/disconnecting it. If its in the return path that will stop it. If its in the feed, wont make a blind bit of difference but you should be able to meter it out.

regardless I think you are going to need the wiring diagrams.

[Range Rover Blues]

The ignition light goes to the engine/alternator, the temp guage would just read max if it were shorted out but it's possible the ignition supply is shorting out on a circuit that goes nowhere near the dash itself.

[Evilgoat]

The ignition light goes to the engine/alternator, the temp guage would just read max if it were shorted out but it's possible the ignition supply is shorting out on a circuit that goes nowhere near the dash itself.

Alternator excitation SHOULD come from the battery lamp, a short there should just jam that on. Again with out the siting diagram I cant be sure of that. The idea is that untill the alternator become self-exciting it draws power through that bulb, hence the reason its on at startup. Not all alternators do this but I would hazard a guess the LR setup is old enough it does. It would also mean your alternator possibly isnt working. Gah I'm gonna go find wirting fiagrams, this is annoying me now :)

Just confirmed that with someone in the know. Short on the supply to the alternator will result in a glowing battery light and nothing comming out of the alternator.

Wiring diagrams on the way...

[Mark_Sims]

I had a problem similar to this. Was caused by the wire running to the towbar socket being pulled a little tight and rubbing on the underside of the car. Hit the right bump and it shorted to the body, the fuse went followed by the dash lights (plus the rest on that fuse).

Mark 

[craigiow]

have looked around the head and no obvious trapped cables there, fuse seems to pop instantly when cold but when warm can last up to five mins  of driving, all lights etc work perfectly when fuse is ok , wondered if it was worse when cold could it be glow plug related ?

[craigiow]

well its all fixed and was a really stupid problem, the metal bracket that holds the dash surround in place was disconnected and swinging behind the instrument cluster  :D