Rear Light Identity Crisis!

[pendry]

Hi all,
Wierd one here - I recently changed the Chamaera's battery, what an arse of a job! Which genius decided that right at the bottom of the passenger footwell was a good place to put it? Why the hell they can't put it in the engine bay like almost everybody else I have no idea! And I won't accept any waffle about lowering the center of gravity giving less body roll as I seriously doubt a 10 kilo battery mounted 6 inches lower would make much difference against a 1.1 tonne car!
Anyway rant over, I finished the job, pushed all the wires into place and refitted the kick panel.
Now I am not absolutely sure if it is a coincidence or not but from around that time I find whenever I switch on my side lights the rear brake lights also come on and whenever I use the brake the sidelights come on too!
Anybody got any ideas? I half suspect an earth problem on the rear stop/tail bulb. As these are not steel cars TVR must have run earth wires that may well come from around the battery / fusebox and I have disturbed a connection.
However the stop and tail lights dont both come on dimly as you would expect, they are full brightness and the indicators are not afected. So maybe it's a short between two wires somewhere.
Does anyone know where to look, what to look for and what colour wires etc?
Cheers, Stephanie.

[trefor]

There are a lot of fuses and relays in the jumble of wiring you will have disturbed - check everything is tightly in place in the loom. Also, the fuse box is on the bulhead above and behind the battery - just out of arm's way - check all the fuses are in place and tightly seated - it's probably something simple if the problem has just started after changing the battery ... I hope.

[p7ulg]

Might be an idea to take it to a competent auto electrician.We had a fault on a Renault van which caused the engine to continue running if you kept your foot on the brake and took the ignition key out.We found the fault quite by accident, someone had changed a brake light bulb and used the wrong type of bulb.I know this was not a TVR and it does not help you, but it shows how weird car electrics can be!

[shpub]

Hi all,
doubt a 10 kilo battery mounted 6 inches lower would make much difference against a 1.1 tonne car!

It actually weighs about 20 Kg and does make a difference.

The rear light wiring plug can corrode and cause interesting disco lights. Try removing and cleaning.

[ribol]

Stephanie,

Can we assume that when you hit the brakes the front side lights come on too?
As we are all allowed one guess, this is mine. The supply for the brake lights comes from the brake light switch and then runs down the car. The supply for the rear side lights also runs down the car. Any short between these two wires at any point would cause the problem you have. I think it is unlikely for these two wires to short out as they run down the car unless they have been damaged in some way so it only leaves two choices.

1. You found both wires near the battery and pinched them together causing the short.
2. There is a short on one of the two rear lamp bulb holders or wiring between the two circuits. Chucked any dead bodies in your boot recently?

Over to you,

Ivan

[tantivy]

'blue string soup - the revenge...' available today on Front Row....

[pendry]

Thanks all, especially to shpub - Maybe I should also get a breast reduction as they weigh a few kilos and are generally mounted quite high in the vehicle!

[ribol]

pendry said: Thanks all, especially to shpub - Maybe I should also get a breast reduction as they weigh a few kilos and are generally mounted quite high in the vehicle!

[Hut49]

pendry said: Maybe I should also get a breast reduction as they weigh a few kilos and are generally mounted quite high in the vehicle!

Gulp! I hope Mungo misses this one! Stop sniggering at the back Jones Minor!

[pendry]

Not that I have ever weighed them you understand!
Does anyone have a wiring diagram handy so they can tell me:-
Colour of sidelight wires, where they originate and the route they take to the rear.
Colour of the brake light circuit wires, where they originate and the route they take to the rear.
And - colour of earth cables for rear cluster, where they originate and the route they take to the rear.
Thanks, Steph

[M@H]

Hi Steph

..just thought I'd hi-jack yout thread with another battery related question.. .sorry..

OK, should there be a strap/bar or similar holding the battery in its tray as if I give mine a decent bit of welly I can shift the battery back into the footwell a bit.. ?

anyone..
Cheers
Matt
93 Chim 400

[shpub]

Battery moving in box is often caused by a smaller lower power battery being fitted. It is normally a tight fit. For a considerably amount of money I can supply a special aluminium bar that will fit the gap and enhance the owner's experience in the way that using genuine ally can only do. Offer subject to finding bit in the scrap metal box. SHPUB reserves the right to supply a bit of plywood instead.

As for the cables, it is the bible but there are no bibles about. I would keep things simple and look at the light cluster connectors and check for shorts and problems there. Simply look for volts when you switch the various lights on.

As for the girlie bits... Definitely your problem.

[simpo one]

'should there be a strap/bar or similar holding the battery in its tray as if I give mine a decent bit of welly I can shift the battery back into the footwell a bit.. ? '

I read this as the battery box being loose to the car, rather than a too-small battery. If I'm right, then someone's probably changed the battery and not bothered/been unable to put the two floor bolts back in from under the car.

If I'm wrong, SH is right!

[M@H]

Noo.. the battery box is nice and snug and not moving at all ..also remember on the early Chim the battery box is above the relay board etc and not on the floor. The battery is pretty tight in there, I just noticed that it can move back an forth an inch or so under intense acceleration and braking..

..basically if there wasn't supposed to be anything there I won't worry as the "kickplate" trim keeps it from going anywhere major..

Cheers
Matt.

Edited to say..

so steve, I see you're making things from special aluminium now.. does that mean you've run out of unobtanium..?

>> Edited by M@H on Friday 8th November 16:07

[shpub]

Not only that... water will be coming through those holes which should be sealed with silicone.