Seat Leon brake lights illuminated when the other headlights turned on.
Variant: Ecomotive 1.6 TDi
Model Year: 2012
Categories:
Electrics, ECU, Warnings & Lights
The brake lights come on when side/headlights are turned on - not 100%, getting 6v at each light. The third brake light is not effected. The lights go to full strength when the brake pedal is applied.
The brake lights work fine when the other lights aren't on. No other lights are effected.
I'm suspecting some wires are touching or a pressure fault between wires but have no diagrams and don't want to start dismantling if this is a problem someone else has encountered. Also, could the supply control panel have anything to do with it?
I was thinking that if the wires were touching, wouldn't the headlights come on when I applied the brake (that doesn't happen), unless the problem is on the supply side of the headlights switch. And my brain is telling me that because the brake lights are coming on without touching the pedal, then the fault must be the light side of the brake pedal switch. Unless, like I said, it's a panel or non-wiring problem.
Gawd, does all that make sense? And am I barking up the wrong tree with my mad ideas?
Cheers any way (if anyone reads this short novel).
The brake lights work fine when the other lights aren't on. No other lights are effected.
I'm suspecting some wires are touching or a pressure fault between wires but have no diagrams and don't want to start dismantling if this is a problem someone else has encountered. Also, could the supply control panel have anything to do with it?
I was thinking that if the wires were touching, wouldn't the headlights come on when I applied the brake (that doesn't happen), unless the problem is on the supply side of the headlights switch. And my brain is telling me that because the brake lights are coming on without touching the pedal, then the fault must be the light side of the brake pedal switch. Unless, like I said, it's a panel or non-wiring problem.
Gawd, does all that make sense? And am I barking up the wrong tree with my mad ideas?
Cheers any way (if anyone reads this short novel).
Posted: Sep 22, 2021 (3 years ago)
Can be caused by wrong bulb type fitted i.e single filament or double filament or incorrectly fitted . Other cause is fault ground / earthing or bulb circuit board panel
Posted Sep 22, 2021 (3 years ago)
Replying to post by whittingehame:
Can be caused by wrong bulb type fitted i.e single filament or double filament or incorrectly fitted . Other cause is fault ground / earthing or bulb circuit board panel
Cheers. They're single filament bulbs. On the Leon, the tail lights are in a separate cluster to the brake lights - brake on the actual car body, the tail lights are part of the hatch.Can be caused by wrong bulb type fitted i.e single filament or double filament or incorrectly fitted . Other cause is fault ground / earthing or bulb circuit board panel
Checked the first obvious earth point, it was clean and solid, but don't know where there may be others (can't find any wiring diagrams anywhere online).
I took all the bulbs out and tested the individual live feed for the brakes and got a steady 6v. I didn't think that would happen if it was the earth, but l know bad earth's can cause all sorts of weird stuff. I'll look again at the earths.
Cheers again.
Posted Sep 23, 2021 (3 years ago)
How come you are only getting 6 volts instead of 12volts at lights ?
Posted Sep 23, 2021 (3 years ago)
Replying to post by Dan:
Cheers. They're single filament bulbs. On the Leon, the tail lights are in a separate cluster to the brake lights - brake on the actual car body, the tail lights are part of the hatch.
Checked the first obvious earth point, it was clean and solid, but don't know where there may be others (can't find any wiring diagrams anywhere online).
I took all the bulbs out and tested the individual live feed for the brakes and got a steady 6v. I didn't think that would happen if it was the earth, but l know bad earth's can cause all sorts of weird stuff. I'll look again at the earths.
Cheers again.
There's 6v at the brake lights when the main lights are turned on. No voltage when main lights are off, buy full 12v when brake pedal applied. Cheers. They're single filament bulbs. On the Leon, the tail lights are in a separate cluster to the brake lights - brake on the actual car body, the tail lights are part of the hatch.
Checked the first obvious earth point, it was clean and solid, but don't know where there may be others (can't find any wiring diagrams anywhere online).
I took all the bulbs out and tested the individual live feed for the brakes and got a steady 6v. I didn't think that would happen if it was the earth, but l know bad earth's can cause all sorts of weird stuff. I'll look again at the earths.
Cheers again.
If I run a temporary earth from the lights to an earth point, do you think that would prove whether it's an earth problem or not?
Cheers again.
Posted Sep 23, 2021 (3 years ago)
Edited on Sep 23, 2021 (3 years ago)
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