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Corsa earth fault

Hi all,

51 reg Corsa... Apparently (not seen it yet) it's developed some odd symptoms. Those are that when it corners hard the brake warning light temporarily comes on, obviously that's low brake fluid. Then a couple of minutes afterwards all the dashboard indicators (warning lights, dials etc.) stop working but the backlight and headlights continue to work fine. The first time this happened they carried on driving and after a bit it suddenly came back to life. The second time (again prompted by hard cornering) they stopped and it wouldn't restart - starter motor worked but it didn't catch. Bump starting it did the trick.

I reckon there's an odd earth fault somewhere that's adversely affecting the dashboard control circuitry but don't really know where to start looking for it. How can I start to diagnose it (competent at using a multimeter)? I replaced it's battery recently (this problem didn't start at that point!) and the earth strap looked fine. The negative lead to the engine block was fine at the battery end but couldn't get at the engine end. Can I get away with just topping up the brake fluid? :)

One other possibility is that I forgot to clean the battery posts before putting the leads on and I remember that they had some deposits on them but surely if that was the problem it would affect everything.

TIA (again),

Peter.

Reply to
Peter Spikings
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Christ, this would be a hard one to diagnose!

Check ALL engine earths, and feed wires, and body to engine wiring looms that may be coming into contact with the engine, or being pulled on when the car corners.

A wiggle test with an assistant, engine running is where i would begin..

Tim.

Reply to
Tim..

I guess that's the first thing to try then :) I wonder why it takes a bit of time before the dash dies though? I hope the bad connection isn't behind the dashboard!

Thanks,

Peter

Reply to
Peter Spikings

Peter Spikings wrote in news:newscache$560jdj$jxi$1 @news.powernet.co.uk:

Could be the fault needs heat to manifest itself, like a dry joint type thing. Good luck finding it, and remember to look for the easy stuff first ! ;-)

Reply to
Tunku

Don't forget a Short Finder can be of enormous help. "Find That Short the Easy Way"

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12V, some short (circuit) finders/detectors: (No standard name yet)
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And, of course, if you do find the brake fluid low, topping it up is less important than finding where the leak is, but I guess you know that.

Reply to
Lin Chung

Ta...

Yes but suspect there's no leak but rather that a garage has done some brake work and not bothered to refill the reservoir after letting some out. Happened to me a while back when I got my rear brake cylinders replaced, dunno how or why but the fluid level afterwards was low enough to make the light come on when going round corners fast. Also when I next replaced all the brake fluid I got loads of bubbles coming out of one of the rear bleed valves when I opened it. Grr.

Peter.

Reply to
Peter Spikings

I've no extra advice to give but I feel you pain, currently trying to track down the reason why all my lights/dash/wipers work better when i stall my window motors, and why straining the engine against a start or the handbrake makes the lights dim. Ive checked all earths with the wiggle test, jumpered the block to the body, measured the resistance of all earths using a DMM. Got the engine out now so makes tracing cables easier at least!

Reply to
Coyoteboy

Or the brake linings are getting low and the reservoir was never filled to max and so now can flicker as the level has fallen. It's not always a huge problem as is made out so often on this group.

Reply to
gazzafield

Good point.

Reply to
Lin Chung

Had the same problem with the brake warning light, turned out to be a bad earth down by the handbrake lever.

Reply to
Les Ross

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