Struggling with rear brake light change

[haymitch]

I've been struggling to change one my rear brake lights. I bought a 382 P21W bulb from Halfords which I've been trying to fit. The first problem I encountered is that the bulb does not turn in the holder as much as the previous bulb, which keeps resulting in it falling out. I didn't realise this the first time so ended up losing the bulb in the rear headlight assembly. Whoops! I managed to fish it but don't think these are the right bulbs. Has anyone encountered this before? Now I think about it, these look like single filament bulbs when what I need are double filament bulbs.

I also can't work out how to get the bulb holder back on. I've lined up the lugs but can't seem to get the holder to twist anticlockwise back in place. I'm wondering whether it might be simpler to take out the headlight and do it that way?

[Forrest]

If it’s for the brake light on a 940 then that is usually combined with the tail light so you’ll need a 21/5w dual filament bulb. Type 381 I think. These usually have bayonet pins set at different depths on each side to ensure correct orientation in the socket. If you’re trying to install a single filament bulb in a dual filament socket the pins won’t line up and it won’t turn properly.

When trying to reinstall the holder in the unit be aware that one of the three lugs is a different size again to ensure correct orientation and make sure the right terminals connect together. It’s best not to remove the whole fitting if you can avoid it since the weather seal may not seal properly when you refit it.

[Laird Scooby]

What he ^^^^^ said except the correct bulb for stop/tail is the 380 and if one has gone, chances are the other one will soon as well.

When refitting, are you sure anticlockwise is the correct direction to turn it? Usually it's clockwise as viewed from the bulbholder side.

Whereabouts in Cambridge are you?

[haymitch]

I'm in one of the villages north of Cambridge near Newmarket

You are right Laird it was a case a turning the bulb clockwise. I tried the process again with the correct 380 bulb and managed to get the bulb back in the car. The brake light still doesn't seem to be working though. The headlight is working again but the brake light does not come on when the brake pedal is pressed. The blown bulb warning light comes on the dash still when I press the brake pedal.

I'm wondering whether it's a case of a bad contact on the bulb holder itself. The top metal contact was a problem to get back on because it was slightly bend inwards.

[Laird Scooby]

First, is the bulb in the right way round? The reason for the staggered height pins is so that the bulb can only go in one way but i have seen countless in the wrong way round. THis pushes the contacts far beyond where they're meant to be resulting in poor or zero contact when the bulb is fitted correctly.

Also it means the tail light is then lit with 21W instead of the 5W filament and the brake light only gets 5W which will trigger the bulb failure module.

If you fancy a trundle along the A11 (or even the back droves) i'll have a look for you. If the bulb has been wrongly fitted in the past, i can usually fix the bulb holders.

[haymitch]

Thanks for the offer that's really kind

In the end I had the garage check it out because it happened to be the MOT today and I thought it best to get it done rather than put the MOT off. A little bit annoying as I'd like to have done it myself. I completed my first oil change last week though so I suppose I should cut myself some slack

Will post the results of the MOT later!

[jpliddy]

hi please do let us know how M.O.T. went .
good luck!

[jonnyf90]

Also you’re better off getting bulbs from unipart rather than halfrauds.

As mentioned previously, it has to be a dual filament 21/5W (unless you have a saloon - then they’re the same bulb for brake/indicator/reverse/fog (21W).
Best to change both as once too 👍

Cheers