BMW 3 Series Compact E46 - Old Car Electrics

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Mon 4 Nov 2013 13:14
BMW 3 Series Compact E46 - Old Car Electrics - meldrew

I have an old 52 plate Compact that my wife had from new and at the market prices it seemed like a good idea to keep it to supplement my bicycle! Today the alarm went off for no apparent reason but went off with the key press from the front door of the house.

On investigation later most of the dashboard lights were on as were the brake lights and the central locking did not work either.

Surprisingly the car started and ran OK with all the lights out but removing the key left all the lights etc still on. Disconnecting the battery turned everything off but reconnecting lit it all up again!

I get a feeling that HJ is right about old electrics but this seems a case of pay up as it is quite a decent car, nowhere near scrap.

Does anyone have a view about BMW electrics both in this case and generally? I know cars don't last forever but my bicycle is a more reliable and cost effective transport for local running about. And I like BMWs too!

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Mon 4 Nov 2013 13:24
BMW 3 Series Compact E46 - Old Car Electrics - jc2

52 plate is OLD??????

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Mon 4 Nov 2013 14:18
BMW 3 Series Compact E46 - Old Car Electrics - meldrew

Ok, middle aged 86k but certainly beginning to show it!

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Mon 4 Nov 2013 14:19
BMW 3 Series Compact E46 - Old Car Electrics - dieselnut

With the weather we have had lately I would be checking for water ingress. Check the carpets, interior fuse box & under bonnet fuse box for any water as a start.

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Mon 4 Nov 2013 16:58
BMW 3 Series Compact E46 - Old Car Electrics - elekie&a/c doctor

The E 46 model is probably one of the most reliable cars Bmw ever made,apart from the later models with the valvetronic engine.Electrics on these are very good with very few issues.As already stated,check the boot for water ingress,especially behind the rear lights and radio/media system (if fitted).hth

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Tue 5 Nov 2013 12:47
BMW 3 Series Compact E46 - Old Car Electrics - meldrew

Thanks all for advice re water. It is all dry as a bone inside.

HOWEVER....... reconnected battery this morning and everything was back to normal!!

Had a look on the web for faulty alarm which covered everything from faulty underbonnet sensor to leaving loose parking change lying around inside!

I do feel that there is something amiss with the electrics so I will get my local electrical expert to plug in his machine and see if anything shows up.

Will report back with any news.

Thanks again.

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Tue 5 Nov 2013 14:36
BMW 3 Series Compact E46 - Old Car Electrics - bathtub tom

Rodent damage?

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Thu 7 Nov 2013 15:52
BMW 3 Series Compact E46 - Old Car Electrics - meldrew

Brother in law had rodents eat his 3 series saloon wiring but this one is kept out in the cold. His was in a warm garage!

Went to garage ( I know them well) who cheerfuly suggested I wait until it happens again. Just wish I had had the wit to take a photo of the dashboard with the lights on.

Even the rear screen wiper has started working again.....!!!

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Thu 7 Nov 2013 18:57
BMW 3 Series Compact E46 - Old Car Electrics - madf

Check all carpets for damp.

Sounds like damp in connectors or dash -peer underneath for rust stains.

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Thu 7 Nov 2013 19:16
BMW 3 Series Compact E46 - Old Car Electrics - elekie&a/c doctor

All the functions mentioned that were problematic,including the rear wiper,are controlled by the general basic module,which is located behind the glovebox.hth

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