My tacho sits at 0.

[Michael999]

Sometimes when driving the tacho drops down and sits on the peg.
Then after 5-15minutes it will miraculously bounce back to normal function.

When its dropped down, it will only move if i give it a sharp rev (4k-5k) where it will spring up to redline and then spring back down to 0.

Nothing else in the dash seems to have any issue other than the lcd screen dimming which goes away with a light tap on the window.

Where should i start looking?

[Michael999]

any ideas? :(

[Morgenster]

If it's erratic it's probably electrical. I'm not sure but I guess the tach needle is operated through variable voltage. Anything dsiturbing the smooth delivery of current can cause this: corroded connectors or wires, etc.

[Ausmpower]

dead or dieing capacitors in the cluster cause this as does dead S.I. batteries.

[Macv]

Shogun reset maybe? Be advised, you'll need your radio code. Thought maybe it would reset capacitors.

[Michael999]

Battery is brand new, looks like i need to find a weekend to push my dash apart :(

[bmw_ryder]

offtopic:my fuel warning light(yellow) doesn't come up to life when i have a few liters.it's very iritating because i don't know for how long i 'll be capable to ride my car.
what could it be?the dashboard capacitors?the bulb is new.
any help will be apreciated :)

[632 Regal]

add fuel?
offtopic:my fuel warning light(yellow) doesn't come up to life when i have a few liters.it's very iritating because i don't know for how long i 'll be capable to ride my car.
what could it be?the dashboard capacitors?the bulb is new.
any help will be apreciated :)

[bmw_ryder]

add fuel?

:D :D :D
thanks man,this solution is known....
i was wondering if you had this problem,what could be the cause?in dashboard or in the tank?the problem

[Javier]

when reserve level is reached. This is what light up the bulb. If you have a new bulb and no reserve light, either the contact is opened or the wiring from cluster to sender (in the tank) is opened. The wire is a Black/Red/Yellow one that departs from the connector in the sender, just outside the tank, colors stay the same up to the cluster.

The connector at the sender is a 5 pin one, 4,5 for the pump, 1 for ground, 2 for this switch, and 3 for the proportional signal for fuel gauge (variable resistor to ground).

Javier

[bmw_ryder]

thanks man,
how can i test the warning light,to see if there is an problem.
what tension can i give to the black/red/yellow wire to see if the bulb illuminate himself,12V is ok?

[Javier]

Javier