I once replaced the circuit board on my instrument cluster (1987 740 gle non-turbo) with a ten dollar ebay part. I kept the original speedometer because I couldn't figure out how to reset the new one. So these are easy to find, I would think, and not difficult to replace. But it sounds like there has not been a certain diagnosis on the battery drain. Where is the load when the car is off, overnight? That may be easy to locate with a meter. Also, if we are talking about a short that is causing the drain, there may even be heat produced that could be felt or smelt. I would even wonder whether, under test conditions, you might put the ammeter between the fuse clip and one end of a fuse and thereby see when one circuit is acting oddly. Not while driving on the road but just in the driveway. This might help you see an intermittent problem and identify the exact circuit.

There are many printed circuit boards, what are they talking about? International back order? What is that? Volvo parts are widely available. Over the last 10 years I have always been able to obtain any part.

Your mechanic(s) sound unsure. Tracking down an unexpected load from an accessory or device that drains the battery is fairly easy. A stereo left on would take many many days to run the battery down assuming the car was not being used during that time. A trunk light not shutting off would kill the battery quickly. However your description in the second posting sounds as if the problem is failure of the alternator charging curcuit to keep the battery charged even while driving rather than a parasitic load while sitting.

The correct diagnostic procedure: Verify that battery really is being charged from alternator while running. Just connect a meter to battery and look for 13.5 to 14.5 volts with lights, fan etc turned on ....real easy. Battery voltage should be around 12.5 volts when car is shut off. If Ok then....
Connect an amp meter in series with the battery and observe if there really is a excess load when car is shut off. There may be a normal insignificant constant load of 100 milliamps or less for clock and any other devices that are pulling current such as alarm systems or standby power for a stereo. These do not use enough current to discharge a 50 or 60 amp/hour car battery except over a very long period of time (weeks).

If there is a significant current load of say 1 amp, pull fuses one at a time until load disappears. This narrows it down to a particular circuit, the rest is easy. No 95% quessing is needed here.

Did these mechanics do this or are they just thrashing around guessing about unnamed printed circuit boards on international back order, new batteries and proper amperage alternators. It should never be necessary to replace multiple alternators and batteries. That has all the hallmarks of a "mechanic" who cannot diagnose and only knows how to throw parts at a problem (and take money out of your pocket). If these guys can't diagnose a battery/alternator/charging issue and know the difference between that and unwanted load they should never attempt diagnosis of the unwanted load. Perhaps a more appropriate career for them would be at the MacDonalds take out window.

Has your charging system ever been properly checked?
Before going any further I suggest you pull your car out of that shop and drive to any Advance Auto, Auto Zone or similar parts store where they will happily test your battery/alternator/charging in the parking lot with a role-out tester free of charge.

If you uncomfortable working around the car find an honest, competant mechanic at an independant shop (not a dealer) who knows, loves and respects our Volvos. This may take some scouting around, for example if you see someone at the mall with an older well maintained Volvo ask them where they go for service.

Good Luck, report back

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David Hunter

my volvo was draining its battery also, but after a few trips to get my battery recharged, I found the culprit was a loose ground wire. Go figure, but after I tightened all the grounds under the hood, everything went back to normal and holding at 12.6 volts

The speedometer/odo are screwy too, and only work sometimes, particularly when it's not too humid. This has progressed recently from the speedo being occasionally jumpy. Also, when the battery power weakens, they are the first things to go (before the lights dim, the radio cuts out, etc). Just thought I'd add that if it helps to confirm the diagnosis.