Number 3 fuse keeps blowing

[Big Nick]

Hi
Noticed the clock was not working so changed the number 3 fuse, blue spark and another dead fuse. Checked the ciggy lighter thinking this might be the cause of a short as it just turns in the dash but it seems ok. Found that my rear speakers wiring had become disconnected so though that they might be shorting out so reconnected. Changed the fuse, blue spark etc etc. Any thoughts?

Cheers
N&Z

[CovKid]

What year Nick and number 3 from which end?

If you can update your profile as soon as, it saves use asking you see - we'll know what you've got and can give a faster answer.

[1664]

Hmmm, think I can see where this thread's heading......

[Big Nick]

Hi Cov Kid
Sorry about that its an 89 Multivan (LHD) no3 from the nearside in (Blade fuse).
Cheers
Nick

[jake1953]

It should be a 15 amp fuse in there. It hasn't been changed to something smaller?

[Big Nick]

No unfortunately not it had a 30 amp fuse in there (which is quite concerning), it does however have additional light wired in but I would not think it would up the requirement from 15 to 30 amp?????

[1664]

As the fuse is instantaneously 'blowing' it's more than likely a dead short. If you are sure it's not the cigarette lighter I'd start looking at the interior van courtesy lights as these have bare metal very close to the van metalwork. Prise the lights away from the bodywork using a small flat screwdriver on the side lip (one in the cab and one behind the sliding door; although I'm not familiar with a Multivan layout so you may have more - tailgate light perhaps?) and leave the units hanging away from the bodywork. You may want to do the same with the door pillar switches too as they are easy and only take seconds to remove. Whatever you do, don't forget the switches are hanging out and slam the doors on them!! Check that the connections at the lights and switches are secure and no wires have come adrift. You may have a vanity mirror light fitted in the passenger sun visor too but I've never had cause to remove that, besides which it's not close to any metalwork so I'd leave it be unless you know how to easily remove it. Insert good fuse and see what happens.

If it still blows, I'd remove the cigarette lighter and isolate the positive feed to it in spite of your opinion it's not to blame as it is a likely candidate.

The reason I'm not pointing the stick at the radio is that it should have an in-line fuse fitted and if it was shorting that would blow. The reason I'm not pointing the stick at the clock is because it's a pain to disconnect.

See how it goes and you should invest in a cheapo multimeter if you don't already have one

[Big Nick]

Cheers 1664, I think you are right about the short. I have checked the interior lights. Not sure about the door pillar switches, do you mean the ones that sense when the door is open? With regards to the ciggy lighter I only did a visual exam so will try again.
Thanks one again to all
N&Z

[1664]

Not sure about the door pillar switches, do you mean the ones that sense when the door is open?

Yep. Only a philips screw holding them in - a cable may have come off and be hitting metalwork or the bare terminals might be touching metal as they are rather a close fit.

I'd check that extra light thats been fitted too

[Big Nick]

Thanks for that 1664, have checked all the lights now, still seems to be a problem, it definitely looks like a short will isolate in turn to id culprit. Will a short damage a multi meter? I am going through fuses like anybodies business.
Cheers
Nick

[1664]

Will a short damage a multi meter?

Depends. Not if the fuse is out or you set it to voltage and connect it in place of the fuse. I notice you're in Narborough which is about 40 minutes from me. Fancy a drive over? I'm bored as it happens, it'll get me off me backside.................

[CovKid]

The T25 fusebox is overloaded in my view, although marginally improved when the blade type was introduced. I was amazed how many items seem to share fuses with other things. I've been pulling some items out to run on their own fuse with a view to fitting an extra fusebox, labelled accordingly. Its fine for items that don't consume much current but certainly on the earlier fuseboxes, the wiper and blower on one fuse seems absurd. I once found myself totally without wipers in torrential rain on the M1 after the fuse blew when I switched on the blower - thats a safety issue so I split those two.

You need to check carefully whats running off fuse 3 and check that nothing has been spliced into that circuit under the dash by a previous owner - not uncommon. This is why I think an additional fusebox (given how many gadgets we all seem to fit these days) - is a good idea. At a pinch, Halfords do a fusebox for £15.

[Big Nick]

Cheers to you both
1664 if I could take a rain check on that, I'm at relations at the mo, but very much appreciate the offer
Thanks
Nick