Hi Volvo Forums-

The instrument panel lights on my 1989 Volvo 240 are not working. I was hoping I might be able to get some guidance from the members here.

The speedometer, clock are parking brake light are working. When the car is first turned various warning lights turn on momentarily (battery, oil, parking brake failure, light failure). I've attached a photo. The odometer, gas gauge and temperature gauge are NOT working.

I've tried replacing all the fuses. The rear taillights are working. I'm not quite sure what to try next. Should I install new bulbs in the instrument panel? Should I try a replacement dimmer? Should I buy a multimeter? I'm enthusiastic but know nothing about electronics. I'd be grateful for any guidance. Thank you!!

 

Dash illumination - There are two bulbs that illuminate the gauges in the instrument cluster, they are positioned somewhat near the turn signal indicators so the left bulb illuminates the left side (clock and 1/2 speedo) and so on.

Allmost all the dash warning lights should come on when the key is turned on. This is to test the bulbs. Once the car is started most turn off when the alternator starts working. Oil light turns off when there is oil pressure.

Odometer is usually bad electronics in the speedo, live without it. Gas and temp gauge - your gas gauge is working in the photo - but both have various problems, a common one being the nuts that hold the actual gauges to the circuit board come loose and create erratic gauges. The temp gauge has it's own special problems with a "temp compensation" board making the gauge lie and be inaccurate. There are easy ways to bypass that part for free. http://cleanflametrap.com/tempFaker.html

2 bulbs are in the instrument cluster, 3 tiny bulbs in the center console with 1 for the fan sw, 1 for the temp slider and 1 in a light bar "shining" down on the top of the rocker switches. Also same type of console bulb illuminates the shifter. Those 4 are tiny 1.2 watt bulbs with no base.

The dash rheostat is easily bypassed to full brightness. Pull the light sw and rheostat **** off, pry that rectangular panel out and you can get to the rheostat to bypass it with a simple 2 into 1 spade connector.

Some of your dash problems could be simple bad connections - the round connectors you will find (after spending 4 minutes to undo the 4 screws holding the cluster in) get poor connections and tightening/bending them back to grip the connecting pins can solve some problems.

BE CAREFUL - there will be an extra unplugged wire behind the cluster (i think it's white with a red stripe) It's not used because you don't have a tachometer. If you find it and find a place to plug it in - you will FRY your speedometer. So only reconnect what you disconnect!

And I think every one should own a multimeter. A decent one costs less than 10$ and there's plenty of stuff to do with them - like making sure your aa batteries are bad before you throw them away, or you have no resistance in a wire.

 

@hoonk Thank you so much for the detailed reply. I was able to make some progress by swapping in a different instrument panel. This fixed the gas gauge and the lights :-) The temp gauge and odometer still aren't working. I may try and replace the odometer gear tomorrow to see if that gets the odometer working. The new instrument panel had a working check engine bulb so now that is illuminated. Is that something I should be concerned about?

Thanks again for your help!!

 

Check the link in my previous post about the temp gauge - The gauge is a simple ohmmeter, the sending unit is a variable resister. (same with the gas gauge) To test if it functions at all - you can (with the key on) momentarily ground the temp sending unit wire - for just a second, you can easily melt the gauge if grounded too long.

Check engine light means there is a self diagnostic code stored in the fuel or ignition control units. A good source for that info is here - https://www.volvoclub.org.uk/faq/EngineOBDCodes.html

Don't count on fixing your odometer.

 

Thanks Hoonk! Great suggestions :-)