Chimaera Brake Light Issue

[Bytesize]

Hi

Just had my yearly MOT torture. Far worse than taking exams yourself !!

So, after demolishing my finger nails over the hour, I still ended up with the dreaded red sheet.

She failed on a couple of things, all light related, so I think "Not too bad!!". The headlight adjustment looks to be a bit of a pain as no inspection plate on either wing, even though my owner’s manual states the use of it to gain access to the headlight!! Confused? I was!!

The other failure point was that both brake lights were not working. I was by myself on MOT day, so rather tricky to test by myself, so assumed they would be ok. Once the family returned I roped in my son and sure enough both were not working. Obvious test was the bulbs but they were ok. Checked the brake light switch and all ok there and have a healthy voltage across connectors.

The other lights on the rear clusters work ok, but the voltage to the brake lights is near to zero.

Think it could be an earthing issue but open to suggestions. I'm assuming as the other lights are ok, that it is not a fuse problem.

Any help would be greatly appreciated ...

[markreilly]

Your inspection plates are in the wing behind the headlights,you need to remove the silka flex and 2 self tappers to gain access.

[Bytesize]

Hi

One would hope so, but I've just got a solid wheel arch on both sides unless TVR have engineered an invisible inspection hatch (or I need to go to SpecSavers!!)

Have read they introduced the inspection hatch on later model.

[phillpot]

Do your wipers "park" ok ?

On my '96 brake lights and wiper park share a fuse, kept blowing coz park switch (sits under the wiper motor in all the water) was corroded/shorting.

[Hughesie]

Could be the brake light switch - pop your head under the dash and above the brake pedal is a small white box, dead easy to sort out, i had this problem on my old Chim and the switch had failed - coule of quid and it should be sorted if it is that...

[Bytesize]

Hi Phillpot, funny you should say that, but yes!! Thought it was another job to do, but not an MOT failure reason, so have left it for now. Will check when I get home. Assume its a fuse on the main fuse panel?!?

Hughesie, did check the switch and everything ok there. 12 volts cross connectors when depressed and zero when released.

[phillpot]

Bytesize said:

Assume its a fuse on the main fuse panel?!?

Yes, 15 amp IIRC but "moves around" depending on age of car/fuse box TVR decided to fit that day

[Bytesize]

Hi Phillpot, On my 96 Chim, its labelled "Wiper/Brake Light" position 18 and is a 20amp fuse. Fuse is fine when checked with meter.

Could it be an earthing problem which is causing both the brake lights & wiper park switch issue or a failed wiper park switch which is having a knock-on effect on the brake lights?

Do you know of any obvious earthing points in the drivers foot well I could use to test?

[phillpot]

Well I'n no auto electrician but on mine all rear lights connect up to a common earth so would doubt its an earth problem if side lights, indicators are ok ?
If you definately have power (12volt) at brake light switch guess my next move would be running a temporary feed from the switch directly to one of the brake lights, see if that works. maybe a bad connection somewhere ? can't remember now but is there a multiplug thing in the void accessed from the flap above the cill, behind passenger seat ?

[lesstatt]

Yes id start with that multiplug, my indicator stopped on one side only and was only showing around 8v, cleaned the plug up which was coated in green fur and all ok now

[Bytesize]

Hi Phillpot & Lesstatt

Thanks for the replies. Success !! You were both right. I had removed the switch, creating a closed circuit and as I was inspecting the connectors behind the flap on the B-pillar (passenger side), they suddenly came on. Cleaned the connector pins plus a bit of WD40 and working a treat now.

Thanks again for all your suggestions.

[phillpot]

just pop a cheque in the post when you get a minute




Could try some of this

Edited by phillpot on Wednesday 19th May 13:06

[drlloyd]

On the earlier Chimaera the back of the head-light unit is accessed through the front grille. Definitely think that the access panel on the inner arch is an improvement!

Daniel

[Jobster]

just to let you peeps know that I had a problem with jut 1 rear indicator not working. Turned out that removing and re-plugging the multiplugs behind the "secret" flap in the B-pillar passenger side fixed the issue. Oh, and I have a Griff so same solution.