I have a 53 Octavia auto estate (L&K) which has suddenly shown a lights failure warning. We've changed what seemed to be a blown brake bulb but the warning still comes on. All 3 brake lights are working. When the engine is on it says 'lights failure' but goes out everytime you brake (coming back on again when you ease off the brake), but when the lights are switched on the message changes to 'brake light failure' which goes out when driving but comes on everytime you brake!!

The only weird thing is that when the lights (side or normal) are on, the brake lights come on (including the top tailgate brake light). Could this be a fuse problem? Unfortunately we dont have the manual with the car and it's a bit different from my previous Fabia VRS.

This sounds more than a bulb / fuse problem.

It is worth noting that the rear lights are very sensitive to the use of incorrect bulbs. Make sure that the bulb you replaced is the same as the new one. Some are twin filament, some single (that still perform both stop and tail functions), some have offset pins, and some have parallel pins. The watts ratings vary too. The wrong bulb can cause unusual faults.

The Octavia has quite a modern and complicated lighting system that monitors the state of the bulbs, hence the warning, a lot of which is controlled by the cars CANBUS system.

It may be something as simple as a poor earth but I suspect something more sinister. The brakes lights coming on with the tail lights isn't a blown fuse or a duff bulb.

The Octavia is known for water leaks into the spare wheel well via the rear lights / rear screen washer which has been known to cause problems in the past.

Plugging your car into a diagnostic machine should throw up an error message which might help to pinpoint the issue.

My recommendation would be to check for water ingress then to swap out all the bulbs in the rear clusters. It'll cost you £20 and take an hour or so but better that than paying an auto electrician to do the same.

If that fails then its time to bite the bullet and get it looked at professionally.

Good luck and remember to let us know how you get on.

Edited 8 August, 201114 yr by silver1011

THat is spooky - I've just got something similar on mine - was on the M62 on Monday and hit the brakes because someone cut me up (trying to overtake me when the climbing lane was running out) and the bulb out warning light came up on the dash but no message on maxi-dot to tell me which bulb and I can't find which one has gone...

Wierd goings on with bulbs can be due to faulty earths. Instead of current flowing back through the chassis like it should, it looks for some other way back, often through another bulb. Do the other bulbs come on at full brightness when it happens? If not, then it could be a dirty/loose/corroded "earth" connection.

Wierd goings on with bulbs can be due to faulty earths. Instead of current flowing back through the chassis like it should, it looks for some other way back, often through another bulb. Do the other bulbs come on at full brightness when it happens? If not, then it could be a dirty/loose/corroded "earth" connection.

My thoughts exactly, the indication of the brake lights coming on when the side lights are turned on points to a bad earth somewhere in the sidelight circuit that is causing the current to flow back through the brake lights.

Ian

Bad earth or water on the wiring loom caused by a leaking rear washer pipe in the cubby hole behind the N/S/R wheel arch would be my guess.