Dome fuse keeps blowing

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parker455
Posts: 430
Joined: Sun Jul 06, 2014 11:16 am
Location: United Kingdom - Essex

Dome fuse keeps blowing

Post by parker455 »

Hi guys,

On my project car, we fitted the new engine and dopey me stuck the battery round the wrong way..

It blew the alternator fuse, various fuses in drivers footwell which I've replaced, and the dome fuse on the frunk fuse box.

Everything else is working great now after replacing the fuses (and of course, switching the battery round to the right way), but the dome fuse blows every time a battery is even hooked up to the terminals.

I've read it could be the radio's aerial causing this, so that's next on the list of things to pull out and try. Anyone else know of any good places to start? The internet provides very little in terms of responses to these questions. I've got my multimeter ready so how would I go about checking? Electronics aren't my strong point..

Thanks in advance :th:
uglee
Posts: 934
Joined: Mon Dec 20, 2004 12:38 pm
Location: Ayrshire

Re: Dome fuse keeps blowing

Post by uglee »

Remove all loads off the Dome circuit which according to the 1990 EWD I have is:

Power Antennae motor
Door courtesy lights+switches
Personal light (whatever that is)
Factory Fit Alarm
Radio/CD Player
Rear boot light+Switch
Active Stereo amp+subwoofer.

With a bulb connected by 2 wires run this across the fuse location terminals, ignition switch on (engine off).

The light should be on, one by one add in the components on the dome circuit checking the light inbetween. When the light goes off that's your dodgy component.

If it's a short in the wiring to the body of the car, with the dome fuse removed and with all the components removed from the circuit check continuity on the dome component harness plugs.

If you get continuity on a components supply wire and the body of the car your loom is damaged.

HTH
oukie
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Re: Dome fuse keeps blowing

Post by oukie »

Hi, I think the personal light is the little round light that goes round the ignition.
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Torero
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Joined: Sat Nov 29, 2008 11:33 pm
Location: Westminster, London
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Re: Dome fuse keeps blowing

Post by Torero »

uglee wrote:Remove all loads off the Dome circuit which according to the 1990 EWD I have is:

Power Antennae motor
Door courtesy lights+switches
Personal light (whatever that is)
Factory Fit Alarm
Radio/CD Player
Rear boot light+Switch
Active Stereo amp+subwoofer.

With a bulb connected by 2 wires run this across the fuse location terminals, ignition switch on (engine off).

The light should be on, one by one add in the components on the dome circuit checking the light inbetween. When the light goes off that's your dodgy component.

If it's a short in the wiring to the body of the car, with the dome fuse removed and with all the components removed from the circuit check continuity on the dome component harness plugs.

If you get continuity on a components supply wire and the body of the car your loom is damaged.

HTH

That's a great guide Lee but whereabouts is the alarm fuse located.

FYI - I have a similar issue to Tom except the fuse isn't blowing but it's running the battery down.
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uglee
Posts: 934
Joined: Mon Dec 20, 2004 12:38 pm
Location: Ayrshire

Re: Dome fuse keeps blowing

Post by uglee »

The fuse for the alarm is part of the 'dome' circuit according to the EWD I have. So if you pull the dome fuse it should kill the alarm system.

I've never seen a factory alarm system and amazed some still work!
parker455
Posts: 430
Joined: Sun Jul 06, 2014 11:16 am
Location: United Kingdom - Essex

Re: Dome fuse keeps blowing

Post by parker455 »

Found it was my door courtesy light switches, disconnected for now but there's a short under the dash somewhere! Thanks for all the help guys much appreciated
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