OBC Display

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randall977
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OBC Display

Post by randall977 »

The display flashes accross (see video) - what's the most likley culprit? Thanks

https://1drv.ms/v/s!ApP9U3GKqHC3icw34zyy--rtKTSbQA
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randall977
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Re: OBC Display

Post by randall977 »

Just been looking at the OBC setup under the passenger dash (UK) - took out the computer unit and cleaned both blocks of contacts...made no difference. The display presumably works but it's not being given the right information?

The car has been off the road with a flat battery for at least 8 years - does the engine need to be run to allow the computer to build up a bank of info? Just clutching at straws really - I can get a replacement unit - but I want to replace the right bit.

Many thanks!
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randall977
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Re: OBC Display

Post by randall977 »

OBC relay is supplying power to the main relay so I know that part is working.

Can anyone see the video in the link I posted? - would really appreciate advice as to the likely cause of the flashing digits - thank you in advance!
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raykoke
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Re: OBC Display

Post by raykoke »

I saw the video.

That's weird!

I'd look for another OBC myself...

Good luck,

Ray
'85 ///M635
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randall977
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Re: OBC Display

Post by randall977 »

Thanks for the reply. I've found one but I didn't want to buy it if everyone said 'it's definitely the display unit'... Will a new (used) one need a code - what about the 'unauthorised start' switch?
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raykoke
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Re: OBC Display

Post by raykoke »

randall977 wrote: Wed Jan 24, 2018 7:12 pm Thanks for the reply. I've found one but I didn't want to buy it if everyone said 'it's definitely the display unit'... Will a new (used) one need a code - what about the 'unauthorised start' switch?
I'm more familiar with the later OBC, in which case the answer to your last question is "no." :)

Looks like a used one is $50 on this side of the pond.

https://www.ebay.com/itm/BMW-635csi-e24 ... uP&vxp=mtr

Cheers,

Ray
'85 ///M635
wattsmonkey
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Re: OBC Display

Post by wattsmonkey »

Never seen that before!

I've got a spare control unit if you want to try it.

It might be worthwhile bypassing the immobiliser function - it's a known pain.

Cheers,

Rob
"Most of it necessary; all of it enjoyable." LJKS
'84 635CSi, dogleg...itbs and supercharger????? Eaton Mess
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randall977
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Re: OBC Display

Post by randall977 »

Thanks Rob, I think that bit works but the rest...not sure. I actually just bought an apparently good one off eBay - hopefully that'll give me normal readouts - we'll see!
wattsmonkey
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Re: OBC Display

Post by wattsmonkey »

No problem at all.

My project car is an early '84 car, so the motronic/obc etc same as yours if you need to compare anything.
"Most of it necessary; all of it enjoyable." LJKS
'84 635CSi, dogleg...itbs and supercharger????? Eaton Mess
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randall977
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Re: OBC Display

Post by randall977 »

My replacement computer arrived today - plugged it in, set the clock and now it all works - very pleased!
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raykoke
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Re: OBC Display

Post by raykoke »

Woohoo!

:) \:D/
'85 ///M635
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