Brake lights gone barmy

[TheBeastie]

I was told yesterday I had a rear light out so took off cover this afternnon (first real chance) and right enough the glass of the bulb had separated from the metal. Hauled it out and replaced with new bulb. Put on side lights to test and all seemed OK but felt they were quite bright. When I was able to get assistant to check if brake lights were working she said no difference. Then when parking this evening I find that with side lights off when I hit the brake all my dash board lights come on and so do my front side lights. I also noticed the bulb covers were hot, presumably because brake lights on all the time

To me this sounds like either an earth has just gone wonky or something somewhere has melted and shorted.

Are there any obvious points to look for or is it just a case of trying to trace back the way?

I did take precaution this evening of removing the 20l jerry can of diesel which sits at the back corner on basis that if something was going to burn I didn't want the jerry can sitting in the middle of it

Looks like my weekend work has just arrived!!!

Thanks for any pointers

Malcy

[western]

or you've fitted the bulbs the wrong way round, tail/stop bulbs have offset pins & the plastic light unit body when worn will allow the bulb to be fitted either way, or you have the incorrect type of bulb, it should have 2 connections on the base & a side connection near the glass part, some have the side connection to far down the metal body & cause the problem you have.

[Matt Neale]

or you've fitted the bulbs the wrong way round, tail/stop bulbs have offset pins & the plastic light unit body when worn will allow the bulb to be fitted either way, or you have the incorrect type of bulb, it should have 2 connections on the base & a side connection near the glass part, some have the side connection to far down the metal body & cause the problem you have.

Agree with Ralph on this one - you've likely put a single filament bulb in the brake/tail light socket - so you're supplying power to the sidelights when you put the brakes on as the bulb is connecting the two circuits.

Matt

[pat_pending]

The brake light is earthing or back feeding through the side light circuit, so..

There is a poor earth on one one or both the rear light units.

The bulb is not located properly in the light unit.

You fitted a single filament bulb instead of a twin filament and the single contact on the base of the bulb has shorted across the two contacts in the light unit.

[JimAttrill]

Fitting single filement bulbs in the stop/tail light can have strange effects - the normal one is that the front side lights come on when the brake pedal is pushed.

The strangest one we had was a TD5 that wouldn't stop if the brakes were on even with the key removed. I told the owner without even looking that he had most likely fitted the wrong bulb. He denied it vigorously, even when I showed it to him. Maybe there is a phantom bulb changer that lurks in car parks

Like the owner who had the blocked oil strainer on a TD5 (and a seized engine) who insisted he had never driven it with the oil light on. I dunno who these characters are trying to fool, it makes no difference to me. Or the bill.

[TheBeastie]

Thanks

Turns out it was wrong bulb. I remember looking to check it was double but did not have my glasses on. Clearly my close eyesight is getting much worse than I imagined!!!

All I need to do now is get my assistant to check brake lights are actually going on since I cannot press pedal and watch back at the same time and there is no reflective surface near.

Malcy

[nas90]

Thanks

Turns out it was wrong bulb. I remember looking to check it was double but did not have my glasses on. Clearly my close eyesight is getting much worse than I imagined!!!

All I need to do now is get my assistant to check brake lights are actually going on since I cannot press pedal and watch back at the same time and there is no reflective surface near.

Malcy

Cut yourself a bit of 1.5inch square wood just long enough to push brake pedal down and jam other end of wood under the trim above the pedals box, simple, turn on ignition, walk round back of truck, with your new spectacles ON

[western]

or if you have a 3 'D' cell maglite torch, use it to press the brake pedal down & jam it to the front face of the seatbox, with the ignition & your Specs on B) that's how I check my brake lights on my 110 & trailer.

[JimAttrill]

I made a handy tool from a shock absorber washer and a piece of tube that just fitted through the hole in the washer, and two pop rivets. The tube pushes down on the brake pedal and the washer is pulled up to just under the steering wheel. It holds the brakes on nicely. The pop rivets through the tube are to stop the washer getting lost when not in use.

Handy tool, because it is instantly adjustable for all vehicles. Maybe I should patent it

[Ivan]

Easy way to check your brake lights is to reverse up to a wall and put your foot on the pedal. You'll see the reflection in the rear view mirror.

Ivan

[TheBeastie]

Thanks guys

All now working perfectly. Daughter checked as gift for getting picked up from work!

Will invest in a piece of 2"x2" since it uses less diesel

Liked the sound of Jim's soon to be patented contraption - may try and build one before the patent kicks in!!

Best wishes

Malcy

[dantd5]

Easy way to check your brake lights is to reverse up to a wall and put your foot on the pedal. You'll see the reflection in the rear view mirror.

Ivan

Ways to check brake lights...

1) To a nearby supermarket, reverse to any of the glass doors and the reflection is enuf

2) Mirror from old bathroom hanging still in my garage.. reverse to it and you see what is happening with the lights.

maybe this will help....