No brake lights

[Tom2021]

Hi everyone,
I discovered yesterday that neither of the brake lights were working on my 2012 ST-X (Spain built, Australian delivered). Replaced both bulbs, tested fuses with multimeter (they were fine but I replaced anyway just in case).

I then tested the brake switch, and had inconsistent readings (turned out to just be user error) so I pulled it apart and tested it and everything was fine.

I put it back in the car and tested it, has 12v going in and when the brake pedal is pressed it's 12v output. So switch is 100% fine.

I had a look under the car and couldn't see any clear frayed wires or anything, and all connections appear to be fine.

Is there anything else I should check before giving up and taking it to an auto electrician?

Any help is greatly appreciated.

 

[ericcs]

test to see if the 12v is getting right to the bulb socket!
if it is, then it could be an earthing issue

 

[Tom2021]

test to see if the 12v is getting right to the bulb socket!

Will check now. I should've mentioned, the tail lights (same bulb) are working.

 

[Tom2021]

test to see if the 12v is getting right to the bulb socket!
if it is, then it could be an earthing issue

Wow there's 12V. At least going to the passenger side.

 

[ericcs]

ok, well that rules out the earth. guess that will mean you will have to chase the wire from the pedal switch then!

 

[Tom2021]

ok, well that rules out the earth. guess that will mean you will have to chase the wire from the pedal switch then!

Stupid question, if there's 12V going to the bulb, why wouldn't they light?

 

[GunMentalGrey]

Possibly not getting light if there is 12v on both sides.

It could be the earth. tail light voltage might be going back through the brake light circuit or some other direction.

Many moons ago I had dramas with a valiant and everything appeared normal but it wasn’t working. There was voltage getting through the wrong way somehow.

 

[[email protected]]

put tempory earth wire on body of globe if power there it will light up

 

[[email protected]]

i had issue power going wrong way, happened were there were multiple earths bolted together, one clip was rusty stopping the earth flow causin power to go through the next earth wire to its globe . each consective globe became dimmer and dimm,er what happens 12v becomes 6v becomes 3v. i have done this on purpose playin around on circuites not connected to car of course
In the past i have left tempory earth wire there as permanent fixture