93 Volvo - SRS Light Stays On - Shorts Alternator

We have an apparent electrical short in the instrument cluster of our '93 Volvo 940 wagon. This frequently results in only the “SRS” and 'Seat Belt" lights being illuminated once the ignition key is turned. The “SRS” light stays illuminated after starting. This apparently shorts the alternator, causing the battery to loose charge after 20-30 minutes of driving. Of course, once this happen the engine fails.

This problem happens intermittently. Many times all the normal dash lights (oil pressure, heat sensors, etc.) come on and go off as normal following starting and the car runs great.

When the “SRS (light) Happens”, we have to resort to PERCUSSIVE INTERVENTION. That is the light can be made to go off by a few well-placed, strong pounds on the dashboard. Unfortunately, my wife is not quite strong enough to succeed with this remedy. (You really have to hit the dash quite hard to cause the light to go out.) Once the light goes out, the car runs great.

Also, FWIW … in the midst all this pounding on the dashboard … our gas gauge no longer works.

We’ve had a couple of mechanics take our dash apart and re-seat all the connections … this seems to help for a day or two, but the problem persists. They’ve suggested getting a new/replacement instrument cluster.

Anyone had a similar problem?

Is a new cluster the answer? Is there a simpler solution?

If a new/replacement cluster is the answer, do you have any recommendations for finding one?

Having just one trouble light on wouldn’t drain the battery after just 20-30 minutes. It sounds to me like there is a deeper issue at hand here. Have the grounds checked, and also have the airbag computer queried to see what kind of an error it is throwing out. It could be many things… even a bad wiring harness going to the airbag in the steering wheel that is grounding out and causing a severe battery drain.

Also check out the web for 940 wagon clubs. There are plenty of them out there, I’m sure your issue has been encountered before. If you decide to ultimately replace the cluster, you can probably find a used one for cheap from a club as well.

Check to see if there is a problem with the power to the SRS system. There may also be a circuit to the alterator from the same power source and that is why the two are related.

Have the alternator tested. A bad diode can cause strange things to happen…