Speedo being odd

Metalbonder · Post by **Metalbonder** » 07 Sep 2010, 17:03

The car seems to be running fine but sometimes the speedo dosen't work. You can cut the car off and then restart it and it will work. It is a 1997 850 nonturbo auto. I'm thinking it may be a short but I'm not sure where to start testing.
Thanks Jake

Post by **jblackburn** » 07 Sep 2010, 18:38

I have a suspicion...twitch the ignition key once you start the car and see if it springs to life. The electrical part of the ignition switch will do all kinds of weird things.

Are your ABS/TRACS lights on?

FCPEURO · Post by **FCPEURO** » 07 Sep 2010, 20:49

+1

If you wiggle the key when this happens and the speedo starts working, then it is the electrical side of the ignition switch. If that does not fix it, and the ABS light is not on, then it is probably just the gauge cluster.

Post by **BEJinFbk** » 07 Sep 2010, 21:49

Or, it IS the ABS and someone pulled the ABS warning lamp out to sell the car...

Metalbonder · Post by **Metalbonder** » 08 Sep 2010, 19:25

The ABS light is on the in the car. The wire going into the ABS module has a short or something in it, you can wiggle it and the light goes off, but once you start down the road it comes back on. I've been driving it like that for a while, the abs seems to be out but not being used to abs it wasn't a real worry to me. It's yet another one of those when I have itme things, but it may move up the list if it is causing this.
Thanks

Post by **Ozark Lee** » 08 Sep 2010, 19:48

The speed sensor is a product of the ABS system. If the ABS goes bad ultimately the speedometer will quit on the '96 and on models.

It depends on where you are wiggling the wires but if it is close to the module then the solder joints inside of the module have fractured. If you know how to solder you can fix it yourself (I have a writeup in the repair database) or you can have the module rebuilt. For rebuilts you have several options from $50.00 from board member Matty Moo to somewhere around $150.00 for Victor Rocha and Module Masters priced in-between.

The stealerships want closer to $1000.00 to replace it so avoid that like the plague

All of the aforementioned rebuilders seem to have good reputations but I have never used them.

...Lee

WeAre06 · Post by **WeAre06** » 08 Sep 2010, 20:15

If you don't figure it out, use a GPS for your speedo. Probably cheaper than buying any volvo parts anyway.

Metalbonder · Post by **Metalbonder** » 08 Sep 2010, 20:44

Cool, its the wires right as they go into the module. I'll try that and see what happens.

Post by **BEJinFbk** » 08 Sep 2010, 21:43

There may well be more to it than that - Read up:
http://home.earthlink.net/~vicrocha/

Post by **Matty Moo** » 09 Sep 2010, 08:07

Metalbonder wrote:The ABS light is on the in the car. The wire going into the ABS module has a short or something in it, you can wiggle it and the light goes off, but once you start down the road it comes back on. I've been driving it like that for a while, the abs seems to be out but not being used to abs it wasn't a real worry to me. It's yet another one of those when I have itme things, but it may move up the list if it is causing this.
Thanks

IF you have a 96, there's a good chance your wires from the pump to the module are losing their insulation. The light will flicker or stay on when they touch. As far as the speedometer going, that's just a matter of the right combination of pins cracking. Get that fixed before it snows.

Wrap those wires with rubber tape or liquid tape. Don't use plain electrical tape, it won't stay on.