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Golfyankee

New Member

• Jul 20, 2018

• #1

hi everyone, I have recently joined as a new member. Hoping to get some advice, my rear brake lights in my series 3 have stopped working. The fuses are fine. I checked the continuity of the brake light switch - multimeter read 1 when pedal is not pressed and the reading changes when the pedal is pressed. I’m guessing this means the brake light switch is ok? I then reconnected the power cable (12 v) to its terminal and checked the voltage coming out the other terminal, it was about 5 volts which seems low. For a time before the rear brake lights stopped working on occasions when driving when I pressed the brake pedal the engine would suddenly shut off but now the engine keeps running when I press the brakes. Has anyone any advice please? Thank you

 

tottot

Well-Known Member

• Jul 20, 2018

• #2

Change the switch,they are cheap enough.but it does seem there is another problem.
As a check have a test bulb [ indicator bulb ] and connect it between brake switch output and earth and see if it lights up fully,if it does not then there may be a problem with the supply to switch [ shorting the ignition causing a cut out perhaps ? ]

 

Flossie

Well-Known Member

• Jul 20, 2018

• #3

Just join the two wires at the switch together to test the circuit.
If they light up then the switch needs looking at.
Your related engine issues sound like a short. Check for chafing of any wires around the movement of the pedal.

 

Flossie

Well-Known Member

• Jul 20, 2018

• #4

Tottot beat me to it.

 

Bobsticle

De Villes Advocaat

• Jul 21, 2018

• #5

Also check the earths behind the rear internal panels. The bullet type ones that rattle about in that pathetic bit of curled tin thats fastened to the tub floor.

 

Rubins4

Well-Known Member

• Jul 21, 2018

• #6

I've seen you can get uprated versions of them. God luck getting the fixing out the old one though

 

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Golfyankee

New Member

• Jul 23, 2018

• #7

Thanks everybody for replying to my thread. After much investigation to eliminate potential causes I know now that the brake switch is fine as is the wiring to the stop lights etc. I have noticed something in relation to the engine cutting out when braking: this series 3 has been wired with 2 ignition switches, one at the steering wheel column and one in the dash. When starting I have to put the key into the ignition at the column and turn it as normal. The oil pressure lights, glow plugs etc come on at rhis point. Then once the plugs are heated I have to use the other ignition switch which has a key permanently in place. Once the engine ignites I release this key and it returns to its original position. What I have noticed is that the engine will cut out when braking if the key in the steering column has been turned too far clockwise. I plan to look at the wiring tomorrow to check out more but has anybody come across this problem before??
Cheers......

 

tottot

Well-Known Member

• Jul 23, 2018

• #8

It is a common problem with old vehicles,you just don't know what mods previous owners have done.

 

dag019

Well-Known Member

• Jul 24, 2018

• #9

Golfyankee said:

Thanks everybody for replying to my thread. After much investigation to eliminate potential causes I know now that the brake switch is fine as is the wiring to the stop lights etc. I have noticed something in relation to the engine cutting out when braking: this series 3 has been wired with 2 ignition switches, one at the steering wheel column and one in the dash. When starting I have to put the key into the ignition at the column and turn it as normal. The oil pressure lights, glow plugs etc come on at rhis point. Then once the plugs are heated I have to use the other ignition switch which has a key permanently in place. Once the engine ignites I release this key and it returns to its original position. What I have noticed is that the engine will cut out when braking if the key in the steering column has been turned too far clockwise. I plan to look at the wiring tomorrow to check out more but has anybody come across this problem before??
Cheers......

Click to expand...

That sounds to me like the steering column switch failed on its final position, (or the wrong one one was used), and rather than correct the problem an additional switch was installed instead. If it was me I would remove the aditional switch (or rewire as a cut out) and replace the steering column switch with the correct and fully working version.
I am currently doing this with a friend who has a series three the previous owner was in the process of installing a push button start "because he liked them". On investigation the reason is the ignition switch did not function properly!

 

tottot

Well-Known Member

• Jul 24, 2018

• #10

My series 3 is the same,someone fitted a button start to get around another problem.Others can not work out how to start it.