Vauxhall Zafira A - Rear bulb not working but bulb ok & fuse ok - Aocal

Hi, this is strange! Wondering if it's happened to anyone else and they got to the bottom of it.

Driver side Brake light not working so replaced the dead bulb with a new bulb. Still not working.

Swapped the fog light bulb into the brake bulb position, brake lights working. Then returned the fog light bulb back to it's original position.

Put the new bulb into the passenger side brake position, working. Put this bulb back into the driver side brake location, not working.

Put new bulbs into both brake light positions drivers side not working, passenger side working.

Put the passenger side old brake light bulb into ther drivers side brake light position, working. Put the new brake light bulb into the passenger side brake position, working!

Thought i'd cracked it, turned the side lights on and the new bulb which is happy to work as a brake light won't turn on as a side light!

Sorry for the lengthy note, something doesn't add up!! Any advice appreciated.

Thanks!

Vauxhall Zafira A - Rear bulb not working but bulb ok & fuse ok - elekie&a/c doctor
Looks like you have a problem with the contacts in the bulb holder .
Vauxhall Zafira A - Rear bulb not working but bulb ok & fuse ok - Aocal

Sorted it. Schoolboy error, i'd bought single filament bulbs and they needed to be dual filament. They also need to be put in the right way- they can go in both ways around.

Didn't even think about it, I removed the old bulb looked at the marking on it "P21/5W" and that's what I went and bought!

Oh well, every day's a school day.