 Weird Electrical problems
Hi! I'm no expert, however, my son-in-law who knows absolutely nothing about cars, has a 2003 R53 S which I sourced & bought on behalf of my daughter (nice 30th birthday present, eh!) he lives in London and was experiencing similar odd lights flashing, window dropping, etc., but mainly rear brake lights coming on after lock up, sometimes side lights, and dash going crazy.
All this drained the battery so he tried the 'local' garage who gave tales of woe and suggested the speedo had been diddled by the previous owner, the diagnostic (generic code reader) gave the fault as "serial module connection -dashboard".
(I researched THIS forum and the BC1 module mentioned by mab01uk seemed to be the culprit.) Son-in-law then took the car, at my suggestion, to a BMW main Stealer for a definitive diagnostic test...£198 charged for the hour! oops.
Together with a long list of sundry faults (not asked for) which totalled......ready?........£6,514 to fix. ha ha.
(Tip:To continue using the car, disconnect the battery earth in the boot and lock up manually, in the morning, unlock drivers door, pull the ring under back seat to open boot and re-connect battery. Irksome, but keeps you going.)
I therefore towed the mini, with my 65yr old wife, 220 miles to Lancashire and said I'll sort it. Found the mysterious BC1 box down by the drivers right foot, (easy! -undo seat belt mount/pull off trim along sill/undo 10mm nut/black box pulls off./#4 connectors from loom/loom is wrapped in daft cloth tape, which is wet, this is the cause, water leaks in via windscreen seals, down loom into BC1 and it also then sucks water up from the wet floor (capillary action). I stripped the cloth insulation off and used proper plastic ins. tape just to band the wires together.)
Now, one garage chap I mentioned this to said it's possible, maybe, to actually dry out the box using heat & hair dryer, then replace the plug in connections (which have a sort of sliding sideways action) this is a long shot but would therefore, cost you nothing if it then works ok. If not......
The next stage, without taking the module off, is to buy a replacement, on ebay used ones are around £55, I got a brand new, unused one for £120! Next it must be taken to a garage (not BMW,unless you're loaded) who specialise in re-programming such black boxes, I went to North West BMW in Horwich, Lancashire and they simply unplug then re-plug new module in, then use laptop to re-program it to your existing keys. They have to take readings from the faulty one first so DON'T UNPLUG IT YOURSELF! your keys won't work with the new module so you'd be stranded. For this they charged £65 but don't quote me on that, I think, ahem, it should have been more. (They give fantastic, honest service and really know their stuff)
Anyhoo, all done, no further problems. It seems it's an acknowledged fault on the mini and apparently the cure is to.....ready?.......wrap it up and seal it in a polythene bag. I'd suggest wrapping self-amalgamating, waterproof electrician's tape very tightly round the wire bunches and then tie-wraps around whatever polybag used, but very tight, water creeps everywhere!!
This was a big mystery to me before, and certainly scared the **** out of my daughter & sil, with hindsight, it's actually very easy.
I'm working on some of the absolutely ludicrous list from BMW as some of it's MOT stuff, which has run out. However, the original main fault was cured for £185 but could be a lot less if using a 2nd.hand module, or even nothing if you're lucky and do as I did. Good Luck. I think this is my first posting on here so hope it's clear and useful. Cheers. Tom.  |
Jan 9th, 2012, 06:47 AM
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