Author Topic: Anything else to try before I give up?  (Read 4752 times)

jimmym105

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Anything else to try before I give up?
« on: 09 April 2017, 11:36:11 AM »
Hi all.

Just passed the mot and done 135k. Now in it's 20th year. Before the MOT I got intermittent rear light or brake light failure messages together with no blown bulbs. Got worse so I swapped out the rear brake and tail light bulbs.  Problem more frequent but still intermittent. Then a rear indicator did go so I thought changing that'd solve it. Changed the rest of the bulbs at the same time so now all bulbs at back of car changed and working. I now get both faults all the time! Anything else that could chuck up the error message? All connections were fine. Thanks

phoenix

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Re: Anything else to try before I give up?
« Reply #1 on: 10 April 2017, 08:02:17 AM »
Sounds like it might be a problem with a poor earth. I don't have the wiring info to hand at the moment but it would be worth tracing back for the light cluster to find a local earth point and see it's not corroded

Audax

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Re: Anything else to try before I give up?
« Reply #2 on: 10 April 2017, 11:49:05 AM »
Are all of the lights at the back of the car actually working correctly? Also are you 100% certain that you have the correct bulbs and have installed them correctly? Both of these things are common reasons to have phantom bulb check messages.

If not remove the circuit boards and give them a good clean up with contact cleaner and wire wool or similar to remove any corrosion from them. Also as phoenix suggested check that all the earths are good. Once you have done all that report back and if it's not OK I'll take a look at the wiring diagram.

sgould

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Re: Anything else to try before I give up?
« Reply #3 on: 10 April 2017, 01:14:58 PM »
I don't know the 9-3 lighting, but on the 9-5, it's possible to push the twin filament bulb in too far, and bend the springy contacts too far down, where bulb seems firmly seated, but it has actually turned further than it should. If that has happened, the two contacts on the base of the bulb can short out between the brake light circuit and the ignition circuit.  Strange things happen then.
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David

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Re: Anything else to try before I give up?
« Reply #4 on: 10 April 2017, 01:46:13 PM »
Each spring I go round giving all light, switches, relay & fuse box and engine bay connects a light spray of WD40. Not sure if it makes any difference, but never (so far) had a problem. Might be worth trying?

jimmym105

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Re: Anything else to try before I give up?
« Reply #5 on: 27 May 2017, 04:25:17 PM »
Been a while until I had a chance to explore. The earth in the corner of the boot near the aerial was corroded to the point that when I pulled it it came off with a bit of body. Need to fill that hole and reearth. Cheers all. Will report back when fixed. 

jimmym105

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Re: Anything else to try before I give up?
« Reply #6 on: 31 May 2017, 09:43:35 PM »
Had to go to the garage to weld in a patch and re earth but all seems well. Thanks for sending me on the right direction chaps!