Dashboard fuse keeps popping

[Juz]

Hi All,

I've got a Defender 90 (J-reg) that popped the fuse for the dashboard (and indicators) a few days after buying it. When I changed the fuse it had a 25amp fuse in it's place instead of the correct one (10amp I think), so I assumed the previous owner just stuck in whatever fuse he had.

I replaced it with the correct fuse and it ran ok for 2 weeks but then popped 3 fuses in 2 days.

I know it's all very vague, but any ideas? Is it a known fault?

Where should I start looking?

Juz

[Steve King]

Unfortunately searching for shorts is never easy. I can only suggest a methodical approach by replacing indicator bulbs one at a time and then if that does not work tracing the wires from where they go behind panels or through grommets etc and checking for worn insulation, cuts etc.

If you are determined to fix it yourself, then take the dash apart and disconnect everything. Then reconnect circuits one by one and re-connect the battery!

Yes a real pain the the proverbial! If you can't find the problem in a couple of hours then it it is time to find a cheap, friendly auto electrician!

Steve

[jacks906]

check the wires that run down passanger side wing around the bottom of the air box my wires down there (altho mines a 300tdi might be differnt) had rubbed on the air box and shorting out, and were blowing fuses for all sorts,

failing that start at the bulb and work back remove relivent fuses and bulds and hope its somewhere simple

quick holiday photo

dave

[110_USA]

I was under the impression that the amp rate listed on the fuse cover was the "constant" amperage and the proper fuse should be double that? However all of mine match except the .5 ones, which are .5 over, with none blown, I just remember reading that info somewhere; also when I changed all of the fuses and cleaned the contacts ( I was having issues ) I pulled out a couple really old fuses (with ink on the glass and little bits of paper inside with amp ratings on them) and I remember at least one saying something like "10 amp constant / 20 amp fuse."

[FridgeFreezer]

Glass fuses are very bad at constant rating, and they usually blow at double their constant rating. Glass fuses, and later ceramic bullet fuses, are bloody awful unreliable things and should be replaced with blade fuses at the earliest possible opportunity. Blade fuses are much better.

For all cases, you should be using the fuse rating that's written on the fuse box, not double - otherwise the wiring may blow before the fuse does. Never never never stick a bigger fuse in because the last one blew. If it blew, it means there's a problem that you need to look at.

I'd put money on this fault being a chafed wire, so look at the loom as it runs through the bodywork, check that all the grommets are in their holes and not perished, check that wires running round any metal parts are clipped up and not rubbing on sharp edges or hot components.

A low wattage bulb in series with the fuse will help save blowing fuses, it will glow when there's a load on the end of the wire (EG a sidelight) but if the bulb glows full brightness and the vehicle lamp stays dead, you know there's a short. If you can, either remove the bulbs or disconnect the plug so that the test bulb should be off unless there's a short.

[western]

never had any problem with my '89 110's glass fuses, so long as the comtact strips are clean & grip well, they should be reliable as any other fuse.