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Electrical problem (420 GSi Turbo)

Fate is preventing me from selling this car. All of a sudden, today I seem to have developed an electrical problem.

Fuse layout here:

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The fuse for the dashboard clock itself (not the clock backlight) keeps blowing whenever I put a new one in. It's rated at 10A and I've even tried a 15, but *boom* it blows immediately. I've circled the fuse that keeps blowing, in the picture above.

With the doors closed and the ignition at position II, if I switch on the courtesy light, the clock (not it's backlight) goes off and the radio goes as if the power has been disconnected. The courtesy light doesn't work.

If I do the same thing after removing the bulb from the courtesy light, both the clock and the radio are OK, but the courtesy light still doesn't come on. The courtesy light bulb tests OK though.

If I do the above after disconnecting the dashoard clock multiplug, it's the same so I can rule this out. I can also rule out the courtesy light itself.

It gets complicated for me here, any ideas? If I take the fuse holder off (which I imagine would be a real pain in the ass), is there anything I should be on the lookout for, and any things I should try and avoid?

Thanks, Steve :)

Reply to
Twinkletoes
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Never replace a fuse with a higher rating fuse, just invites trouble. 15 amps flowing though wire rated at 10 amps will cause a fire.

Courtesy light curcuitry at fault

Obvious, no explaination needed

Are you sure ?

I would start with the courtesy light first. I've never actually seen the wiring diagrams for the 200/400 series. However, does the courtesy light come on normally via the doors opening? Is it just when you manual operate the courtesy light when the problems occur? If so, dismantle the courtesy light, check the operation of the switches contained within.

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Reply to
Demure Guise

On 05/04/2004 23:55:28, in alt.autos.rover, Twinkletoes licked his pencil and scribbled in message

You have run down the faulty system. The interior light circuit is busted. It could be a simple broken wire (have you been working on the wiring looms at all?), but you say this happens with the light switch too, so I would look at the interior light delay relay, if it is fitted to your car. This is usually located in the fuse box. Simply pull the relay out and replace with another. (If the relay is removed the problem of blown fuses may disapear, confirming the fact that the relay is shot)

HTH

Reply to
Mosh Pitt

IIRC, the interior light delay/dimmer function is all controlled by the MFU (Multi-Function Unit). Maybe it is this (or, at least, the relay within) that is faulty?

It's not uncommon for the MFU's on these to go wrong but as they're cheap as chips from most scrappies it will be an easy fix. There is a self diagnostic function for the MFU but I can't remember how to access it off the top of my head. Hold down the heated rear window switch whilst turning the ignition on or something?

HTH

Reply to
Michael Cotton

Thanks for all your help, after 5 hours I fixed the problem. Pulled a carrier bags worth of old alarm/phone charger stuff out of the car, tested the MFU but that was OK anyway, and now it all works. The only casualty was the bulb in the clock which has now died, I'll pick one up tomorrow.

Now I've fixed it I can sell it with a clear conscience - see seperate post.

Cheers! Steve :)

Reply to
Twinkletoes

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