Electrical Gremlins? Tacho & blown light-light

[Chrispy]

Noticed over the last couple of weeks occasionally when I start the CSL that the little yellow lights on the tacho don't light up when cold, just the last one and the red lights as if it was fully warm. Idles and drives fine, everything feels normal. Temp gauge shows cold and works fine too...

Also sometimes the blown light bulb warning light comes on too. All the bulbs appear to be fine and sometimes it goes out after a few minutes or driving - or it stays on for the whole trip. Sometimes restarting the car stops it coming on.

Haven't been doing anything weird to the car, no hosing engine bays or dicking about. Just driving. Did about 500k's in the last 2 weeks as the Audi was playing up and waiting on parts from the stealership.


Any ideas??

[Chrispy]

Anyone got any clever ideas?

[alexk]

The lights in the rev counter are probably burnt.

You are getting warning for which bulbs ? Front/rear ?
Sometimes there is no good contact and as you hit bumps etc they make good contact.
It's best when you replace them.

[Monkey]

Only way to rectify the instrument cluster issue is to replace it. Unless someone knows a company that can repair it? I know when I worked at Munich Legends we used to get the pixels fixed in E39's etc by a company, but I don't recall the name. Think they're about £400 plus Vat

As for the bulb, which corner is it? Sidelights are prone to sporadic failure before going completely, the rear light clusters can burn out in the plugs.

[glendog74]

Only way to rectify the instrument cluster issue is to replace it. Unless someone knows a company that can repair it? I know when I worked at Munich Legends we used to get the pixels fixed in E39's etc by a company, but I don't recall the name. Think they're about £400 plus Vat

The dash on my LSB M3 daily started to play up a while back and it ended up being replaced on AUC warranty - cost around £750 all in iirc...

[Chrispy]

The lights in the rev counter are probably burnt.

You are getting warning for which bulbs ? Front/rear ?
Sometimes there is no good contact and as you hit bumps etc they make good contact.
It's best when you replace them.

The tacho lights come on sometimes. Not like they are always out. Every 3rd start or so when cold they don't all light up.

Front left bulb warning light.

I'll have a look at them when I'm back from site.

[Monkey]

The tacho lights come on sometimes. Not like they are always out. Every 3rd start or so when cold they don't all light up.

Front left bulb warning light.

I'll have a look at them when I'm back from site.

Change the n/s/f sidelight bulb then, almost certainly the cause of the intermittent bulb failure.

Definately an internal cluster fault.

[NBTBRV8]

You should be able to do a self test on the cluster. If not a dealer can check it.

[_Nathan_]

Assume cluster needs to be codes to stop tamper dot from coming on if replacing with used one?

[shane@mbtech]

I have a cluster here if of any use.

[shane@mbtech]

For m3, not CSL but can't see any difference ?

[_Nathan_]

Will be the same, just need to work out the deal with swapping them without activating the mileage tamper dot as I believe mileage is stored in the cluster along with ECU and lcm and they all need to match?

[Chrispy]

Soooo, the rev counter is working perfectly this weekend.

And turns out the front left parking light was blown. That's a little embarrassing.

See how the tacho behaves over the next little while...