OBC "bong" fault

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steve_k
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Post Thu May 31, 2012 4:25 pm

A bit hard to describe this one but here goes.

had the car (325i) off road for just over a week while I did a headgasket, cylinder head swap, cambelt change, tensioner & water pump.

got it all back together today & when I put the battery back on I could hear the OBC bong chiming constantly & the OBC reading minus 30C.

even when the car was running I could still hear it.

anybody got an idea what it could be? & how to stop it?

don't fancy going out to the car tomorrow & finding a flat battery.

help me out here please folk's.

TIA.
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
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BenHar
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Post Thu May 31, 2012 4:41 pm

Maybe you have disconnected the temperature sensor somehow?

Ben
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steve_k
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Post Thu May 31, 2012 4:56 pm

BenHar wrote:Maybe you have disconnected the temperature sensor somehow?

Ben
I honestly don't think I have.

this is going to make me sound a bit thick but..............

where about's is that?
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
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BenHar
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Post Thu May 31, 2012 4:58 pm

It's in the valance or brake duct at the front left. The loom runs up the left hand side of the engine bay.

Ben
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steve_k
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Post Thu May 31, 2012 5:02 pm

Cheer's for that Ben I'll go have a look & fingers crossed it's an easy fix lol.
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
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Brianmoooore
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Post Thu May 31, 2012 6:41 pm

steve_k wrote:
BenHar wrote:Maybe you have disconnected the temperature sensor somehow?

Ben
I honestly don't think I have.

this is going to make me sound a bit thick but..............

where about's is that?
I think you have! Wire might have been partly rotted through at the plug and has been broken.
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steve_k
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Post Thu May 31, 2012 7:18 pm

Brianmoooore wrote:
steve_k wrote:
BenHar wrote:Maybe you have disconnected the temperature sensor somehow?

Ben
I honestly don't think I have.

this is going to make me sound a bit thick but..............

where about's is that?
I think you have! Wire might have been partly rotted through at the plug and has been broken.
cheer's for that Brian.

any ideas about an easy fixin the mean time to stop the sound from driving me mad & to stop the chiming from draining the battery??
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
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steve_k
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Post Thu May 31, 2012 8:57 pm

Bump bttt.

anybody got any ideas for a quick fix??
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
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Brianmoooore
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Post Thu May 31, 2012 10:27 pm

Gong should only sound when the ignition is on, so shouldn't drain the battery, and, IIRC, should only sound once.
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steve_k
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Post Thu May 31, 2012 10:37 pm

Soon as I turn the ignition on it goes off, not once but a constant drone thats why I said about it draining the battery.

any idea how to cure it? Just disconnected the negative lead for tonight.

I really could do with a quick & easy fix ;)
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
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Brianmoooore
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Post Thu May 31, 2012 11:11 pm

The 12 button OBC reads -30 degrees when the temperature sensor is disconnected, but should only sound the gong once.
Connecting the trigger wire on the gong to earth makes it sound repeatably, as you describe, but an E30 OBC should only supply a brief pulse, to trigger it once. E30s built for some other markets use the gong for other purposes, and some of these may run the gong continuously, but not on UK cars. Perhaps your OBC is and has been faulty for some time. It would only show if the temp. dropped below 3 degrees, or you use the 'speed' function.
You can silence the gong by dropping the under dash cover and unpluggiing it.
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