No brake lights, indicators, wipers....coincidence??

[mattinhertford]

Hi all,

All at once my brake lights, indicators, and wipers don't work. Car starts fine, side lights and headlights all work, and rear red lights come on when sidelights/headlights are on.

I've a multi tester so will do some diagnostics tomorrow but anyone had this before and can short cut where i should start?

Thanks

Matt

[bmcecosse]

The fuse has blown! But to find out why.... is your task.....

[mattinhertford]

Roger that, the challenge is on

[mattinhertford]

Sorted, i wish i could say it was expert investigative skills......but it was just beginners luck

I did check over a few wires and connections, especially the rear lights as I had a rear wing off recently, so had a rear lamp cluster off as part of that, then i just stuck a new fuse in and it all works!!......and still works now, so i'm just going to accept the 'luck'

But the brake lights don't work ....i've checked the brake switch (the one in the engine bay) and that works fine, but testing the wires leading to it there is no power so will work backwards from that tomorrow.

Matt

[mike.perry]

How did you check the brake switch? You will not have any power to it until you press the brake pedal. If there are no brake lights when you press the pedal then connect the two terminls with a piece of wire and press the pedal again. If the lights work then the switch is knackered

[bmcecosse]

Ehh?? There is always power at the switch!!!

[simmitc]

I agree with Roy. One of the wires to the switch should, if the fuse is OK, be live. The other will be going to the lights at the rear of the car. Joining the two wires will bypass the switch and confirm that all except the switch is OK. Operating the brakes in this mode will make no difference to the lights.

[alexmcguffie]

Simmitic is correct, but there isn't always power to the switch. The power will only be there when the ignition is turned on.

If you tested the switch with a multimeter it may give a false reading on resistance as multimeters have a relatively high impedance which can 'mask' faulty contacts. The contacts can break down when passing a representative current and effectively become an open circuit. Try measuring the voltage at the switched side of the switch relative to ground.
.

[bmcecosse]

Well yes - power when the 'Ign' is on - I took that as read....