Is this DIM failure?

[putty_thing]

Hi chaps,

Wonder if someone could shed some light on a problem that has appeared on a 2000 P2 V70.

From the research I've done (reading lots of Volvo forums) I was convinced the issue was a failing DIM but have just spoken to a chap who does the repair he's not so sure it is failing so I'd like to get the opinion of the Internets please.

I've got the following symptoms:

Tachometer jumps around a lot on idle, when accelerating
Dash shows an SRS fault
Odometer is almost unreadable (dark) - suspect this is a bulb

As an aside, I've also got an issue with the speedo not functioning and ABS codes being logged on the OBD but believe this is more likely to be the ABS module.

Thanks!

[graemewelch]

mrp should be along shortly, he loves threadson dims

[putty_thing]

mrp should be along shortly, he loves threadson dims

His name did appear in a lot of the threads I read!

[Liddo]

Ive heard / read issues like this COULD be a bad earth, or faulty ignition switch?? DIM failures are normaly clocks going backwards and odometer resetting to zero (first signs)

I may be wrong though :D

[M-R-P]

It's possible although you might just have a cluster of smaller problems that all club together to look like DIM failure.

Speedo not working and ABS faults... you probably have a dodgy ABS sensor or reluctor ring(s)

Dark screen.. probably a duff bulb - have you tried thumping it?

The twitchy tacho and SRS fault could be a failing DIM but from experience it's almost always the info screen and/or trip screen that fails first, then random lights. 99% of the time, the dials fail last. (a failing DIM can also trigger brake warnings and a few other seemingly unrelated errors)

You won't get rid of the SRS light/warning without a proper reset unfortunately but the first thing I would do would be pull the negative off the battery for an hour, remove the DIM and check the contacts are clean on the green plug socket on the back and plug it back in (but don't refit the dim). Put the key in ignition position II and reconnect the battery (this stops the airbags deploying). Then start the car. If the needle is still twitching, grab each end of the DIM and twist it gently to see if it starts to behave. If it does, then the DIM is on it's last legs. A trick I used for a while was to wedge some paper behind one corner of the DIM before screwing it back in, just to keep it a bit twisted.

[M-R-P]

Hold the "read" button on the stalk and press the foglight button to bring up the stored DTCs in the DIM, cycle through and look for "DIM - READY" if it says ready, the DIM is fine.

[putty_thing]

Awesome, will try these over the weekend - thanks chaps :)