For a while now I've been getting the bulb out warning light coming on periodically when braking. Checked the brake lights and sometimes they are fine, other times the lower two and just the outer two of the high level are on. After reading up on here I concluded that it was probably the brake pedal switch, so acquired one from the dealers yesterday and set about fitting it. The new item didn't work. Reconnected the old and got the same problem, so refitted the new and it still didn't light the lights. The the glow plug light came on (I know this is just a spurious fault). So, just popped back and got another switch in case the new one is faulty and the replacement doesn't work either, and now when I refit the old one the lights stay on permanently. The part number mentioned on here is 1J0 945 511 F and is green, but the latest and only switch listed supplied to me by my dealers is 6Q0 945 511 and is black. Should I try a ECP or GSF cheapo switch, or am I resigned to booking it in for a wallet rape ?

Have you actually changed the brake light bulbs?

I've experienced an intermittent bulb warning caused by duff bulbs

If it was the switch, A new switch should have sorted it, But you make no mention of renewing the bulbs!

The lower two are your taillights!

From the top,

N/S O/S

Brakelight-------Brakelight

Indicator---------Indicator

Reverse---------Reverse

Taillight----------Tail & Foglight

The bulbs are fine and illuminate as expected. The high level unit sometimes lights fully, but often just the outer 2-3 LED's and this allies with the light fault warning. Just managed to refit the new dealer part and got back to square one, with working brake lights but the warning and some LED's not lit, so at least the car is safe to drive now. EPC part which was identical to the old switch didn't work, giving the same result as the old part in leaving all brake lights permanently lit. Will remove the high level unit and connect directly to the battery to see if all lights still work, which I expect they do. Quite where the fault is now I don't know, but probably in a loom somewhere, maybe in the tailgate bridge.

Noted, But have you changed the bulbs out for new ones, Or at least tried the reverse bulbs in their place?

For all intents and purposes the bulbs may look OK and occasionally work as required, But could still be faulty.

How many times have you heard of people taking their cars to a garage to have a fault rectified, Only to be told "The fault couldn't be replicated"?

A faulty switch will throw the glow plug light

2 Faulty or blown bulbs will dimly illuminate the outer LED'd on the highlevel brake light!

Will swap over a couple of bulbs later to see.

Swapped over both brake bulbs with both rev bulbs, no difference. Had a fiddle with the high level unit and it briefly fully illuminated, then reverted to the outer 3 and dim.

Now removed high level unit and tested it with a 12V DC supply, absolutely fine. Same at 6V, but at 3V it replicates what is happening on the car, dim and outer 3 LED's only. So, somewhere my car is losing volts on it's way to the HLBR ?!?!??!?!?!

Refitted HLBR unit and got the dodgy illumination, then fully lit for a minute or so, then back to dodgy. Given up on it for today.

Going to run a feed from one of the bulbs to the HLBR to see if that works.

Check all the connections at the rear and clean up, Clean the bulb contacts and the cluster, Check as much of the wiring you can get at!

Other than that I'm stumped!

Good luck hope you get it sorted

Thanks for your input. Will try the HLBR connected to the bulb feed as a last resort. After that it can stay as it is !

Well, it's fixed itself. Not had a beep or warning light for 3 weeks. No idea what's changed, but glad it has

And it's back again. Seems to do it when the brake is held on for a while as if maybe a wire is almost split and the resistance builds 'til it eventually trips. Again the lights all seem to work OK.

It sounds like a bad connection mate take bulbs out clean connection then put Vaseline on connections

Had all the bulbs out last time to no avail, i think a wire may be trapped, splitting or grounding somewhere. I have had the back seats out a few times for when I go on track, so might have disturbed something. Gonna have a good nosey, and if that doesn't work I might run my own wiring from the plunger switch direct to the bulbs to see if it cures it.