Brake light woes
Brake light woes
Author
Discussion

Don1

Original Poster:

16,846 posts

238 months

Monday 13th August 2007
quotequote all
Ok, having a good run with a biker, and he informs me that my brake lights aren't working. So I dig out the bible, and check the fuses (damn, that's HORRIBLE back there), and they are good. Check the pedal and the contacts there - all good. So I'm stuck - what could it be? (You have just witnessed the extent of my spannering).

Cheers all.

StreetDragster

1,575 posts

248 months

Monday 13th August 2007
quotequote all
Is there voltage at the brake light bulb terminals with the pedal depressed?

Thanks

Matt

Cider Andy

1,889 posts

255 months

Monday 13th August 2007
quotequote all
How did you test the brake light switch at the pedal? A multimeter's best, but you can disconnect the two wires and join them together, switch the ignition on and see if the brake lamps are lit.

There's another simple reason that tends to get overlooked: it may be that both brake lamps have failed. It's surprising how frequently this happens with brake lamps and headlamps until you consider that they probably came from the same batch and are always lit for equal amounts of time.

Don1

Original Poster:

16,846 posts

238 months

Monday 13th August 2007
quotequote all
Andy, No, I didn't, something to do. Volt meter? Whatawhater? (I can guess what it is and does, just don't have one.... In other words, no!)

OK, so check the bulbs and see if I can find out if a current is being connected when the pedal is depressed?

TVR keith

1,913 posts

252 months

Monday 13th August 2007
quotequote all
I assume that you have checked the bulbs.Also that the other rear lights work thus eliminating a faulty earth.
On the brake pedal there is a switch which is a Vauxhall item and is known to fail often on those cars.
Unplug the wires from it and bridge them with a paperclip making sure that the clip cannot touch any metal parts and short out. With the ignition on the lamps should be on.
If they are, check that the plunger on the switch is being operated by the depression of the pedal. Assuming that is OK and they don't light go to a Vauxhall dealer and get a new switch.
If with these checks the lights don't work, temporarily run a wire from the battery positive terminal to one of the wires you disconnected from the switch.
One of the wires at the switch is connected to the lamps, when you feed that they should work. Assuming the lamps now work the circuit to them is OK and the fault is possible at the fusebox end, if not, it's the wiring to the rear is where the fault lies.
If you connect power to one of the switch connections and reconnect the one to the lamps, then operate the pedal, the lamps should now work.
My money would be on a faulty switch. I don't think they cost much and it might be a lot easier for you to change it than do the other tests

Don1

Original Poster:

16,846 posts

238 months

Monday 13th August 2007
quotequote all
Thank you Keith, and all - will do all the above.

shell320

131 posts

234 months

Monday 13th August 2007
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Just had the same problem. It was the switch.

They are problematic and I repaired the switch last year but being plastic, the hosing distorts and then the plunger snags and doesn't allow the contact to make properly.

crackedfinger

1,569 posts

259 months

Monday 13th August 2007
quotequote all
If the switch, fuse & bulbs are OK - try the little flap behind the passenger door where there are connectors for all the wires that goto the back of the car - these can come unplugged/ dirty.

S4CJO

429 posts

289 months

Monday 13th August 2007
quotequote all
I had a cracker with this when it went for MOT and having tested the lights found the off side rear not working. Checked all the usual but no joy. Just by chance while wife was pressing on the brake, I held the rubber sleeve at the rear of the light and it flickered on. Eventually I drilled out the three rivets to find the main feed cable had hust dropped out of the holder and was loose. Pushed it and the bullet back into lamp holder, re rivet and all fine and glowing again.

IainG

69 posts

254 months

Monday 13th August 2007
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Another area to check is in the access panel for the passenger door locks. I lost my brake lights at my last MOT. Fuses OK, switch replaced and bulbs OK. A 12v circuit tester was useful! Connection under the access flap was the problem.

macdeb

8,760 posts

285 months

Monday 13th August 2007
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Moneys on the switch, have had two break. They look ok in situ but when taken off have been able to pull apart.

Don1

Original Poster:

16,846 posts

238 months

Sunday 26th August 2007
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After a working holiday on the white isle, I have been able to get my hands on my PAJ. Ok, it is the switch, without a doubt (did the bridge thing).

BUT I am a large bloke, and I'm having trouble getting the switch off. Any tips, and does anyone have the Vauxhall part number please?

Cheers all - together we'll get through this! wink

awager

204 posts

257 months

Monday 27th August 2007
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I had this happen on a tour of France couple of months ago.
Last thing I checked was the switch at the pedal and of course it was this
that was knackered.
I just took it apart, cleaned and adjusted the contacts and all fine now.


TVR keith

1,913 posts

252 months

Tuesday 28th August 2007
quotequote all
Don1 said:
After a working holiday on the white isle, I have been able to get my hands on my PAJ. Ok, it is the switch, without a doubt (did the bridge thing).

BUT I am a large bloke, and I'm having trouble getting the switch off. Any tips, and does anyone have the Vauxhall part number please?

Cheers all - together we'll get through this! wink
I am sure that if you remove it and take it to a Vauxhall dealer they will fix you up with a new one, as has been said they fail often so any dealer should have it in stock.
With regard to access I had a similar problem getting to the O/S nut holding the top of the dashboard. I made it a lot easier by removing the steering wheel. Don't take the whole thing off, just remove the allen screws that hold the wheel on to the centre boss, very easy to do and makes a big difference

Don1

Original Poster:

16,846 posts

238 months

Tuesday 28th August 2007
quotequote all
Cheers, but any tips on how the switch is actually connected to the brace?

RumbleBee

333 posts

236 months

Tuesday 28th August 2007
quotequote all
I had the same problem, but didnt need to replace the switch, it was just snagging and not activating when the pedal was pressed. A smear of grease and a good wiggle and its right as rain. Also worth checking if the bracket has got bent, mine had. Worth bending it slightly so that the brake lights come on just as you touch the pedal. I checked this using a mirror at the back of the garage and just tweeking the bracket with my hand.

Don1

Original Poster:

16,846 posts

238 months

Wednesday 29th August 2007
quotequote all
I'll have another play with it, but does anyone actually know how to remove the white plastic switch, or do I have to disconnect it from the pedal end?

TVR keith

1,913 posts

252 months

Wednesday 29th August 2007
quotequote all
Don,
Just been out and had a look at my one. The white brake light switch is secured to the bracket with a hex nut. Cannot see why you would not just remove this and the switch will come out. Did actually take a pic of it but cannot upload, it says the bandwidth has been exceeded

Don1

Original Poster:

16,846 posts

238 months

Wednesday 29th August 2007
quotequote all
Keith, you're a star. I'll have a go at it over the weekend.

Don1

Original Poster:

16,846 posts

238 months

Saturday 1st September 2007
quotequote all
OK, Vauxhall have proved to me what I have isn't a vauxhall part - any ideas? (Finally got it out, apart, atogether for a partial success - so any further ideas please?)