Hi All:

I have a 1993 240 DL Wagon which usually runs great. A few months or so, the battery died so I had it replaced. Now, the battery is routinely discharging; here are the symptoms:

When I turn on the ignition all dashboard lights come on as they should so I know the "Battery" light works.

If I charge the battery overnight on a battery charger, the car starts right up, no problem. Once started, all of the dashboard lights go out, as expected. Then, after driving for a while, the first thing that happens is the SRS light will come on, but the car continues to run fine. Then, I notice that when I hit the brakes, the radio cuts out, (probably the brake lights are too much draw an a discharging battery). Once I get to that point, if I stop the car and turn the engine off it won't start again; the battery is dead.

If I recharge the battery on a charger again, I can duplicate the entire process, exactly the same.

So, the battery is obviously discharging and the alternator is not it charging properly. But if the alternator is not charging, why does the "battery" light on the dashboard not illuminate?

Is this an alternator problem or a wiring problem? Maybe a ground problem? I know the 240 has an "onboard" voltage regulator (built into the alternator) and I can get a new alternator at NAPA for $119 and I don't mind doing that but I don't want to do it if it's not going to fix the problem...

Any thoughts?

 

Have you tested the alt. output with a multimeter? It's obviously not charging or not enough... The BAT light is very important as it "excites" the ALT to start charging. The SRS comes on due to the drop of voltage, it's very sensitive, it is a result than cause.

 

Thanks for the reply.

What's the best way to test the alt output with a multimeter? do I need to disconnect any leads or just test across a couple terminals? Which terminals? What amperage / voltage should I be looking for?

I assumed the SRS light was just an indicator of voltage drop, a symptom, not a cause but I am surprised to hear you say that the Batt light actually causes the Alt to start charging. Therefore, if a wire to the Bat light is loose, that could keep the Alt. from charging. Is that correct? Where can I look for problems?

Finally, I have seen on other forums that broken connections on a dash circuit board may create similar problems, which were solved with a simple solder... perhaps this is related to the Bat light issue... have you heard of this?

Thanks again.

 

Exactly! The BAT light has to come on AND go off for the ALt to start charging. Sometimes a faulty circuit board (cracked) will cause the warning lights not to work right and this will keep the alt from charging... So, just put the multimeter leads on the terminals, set it at 20, and it should read about 13,5 volts while the engine is running. Engine OFF, battery should have more than 12Volts to be able to start the car. I sometimes do the following: I run a wire with a bulb between the small red terminal in the back of the alternator and the - terminal of the battery, when the ignition key is ON the light should be ON, and then go OFF when the car starts-this gets the ALT charging as it acts like the dash light. Also, revving the motor to 2,500 RPM is supposed to get the ALT charging in case of the light failure, so try that, too.

 

I have a 1992-240 wagon. I have the same problem in that the car operates great with no problems for 6 weeks or so, then when I am driving the SRS light comes on, the car will eventually start to slow down and when I pull over to stop, the car will not start again. The last time it happened, I had the car towed home and then the tow truck driver checked the battery. The battery showed almost a full charge but not enough to crank the engine. In the past, the battery seemed to be completely dead and I could not jump it off using another car. Then the driver showed me a trick. He took the key out of the ignition, locked the door, unlocked the door, inserted the key into the ignition and the car started easily using his portable battery charger. It seems that there is a anti-theft feature that was preventing the car from being jumped off. Once you locked the car and re-opened the door, this anti-theft device is disconnected and you can jump start the battery. Since that time the car is starting without problems. I realize that there is some small drain on the battery somewhere that is not easily detected. Until the car is repaired, I just make sure I have a fully charged battery jumpbox with me at all times. Good luck to you and hopefully you will discover a solution that might help us all!

 

Where is this BAT light? I am having the same problem. My alternator and battery all checked out fine today at both O Reilly's AND Auto Zone.

I am perplexed.

 

The BATTERY light is one of the warning lights on the dash, the symbol I believe on your car is a battery picture--it should come on when the key is in II position (all lights ON), then go OFF as soon as the car starts.

The Volvo charging system is rather straightforward but it seems to perplex a lot. The battery is charged by the alternator, the LIGHT has to come on to get the process going (the tricky part). Of course, the joker is some type of wiring fault/short in which case all bets are off. With all the poor old Volvos running out there with "custom" wiring work due to the owners modifications manias, well, the wiring problems are a bigger problem than they should be.

In the cases above, probably the alternator's regulator is at fault, just the two brushes on the side needing to be refreshed. I personally have never changed an alternator as there is not much to it besides the bearings and the brushes. The bearings usually last many hundreds of thousands of miles... Shops won't tell you that for obvious reasons.

 

I have already had my battery AND alternator tested at Oreilly and auto zone and they ckd out ok. If the brushes on my alternator are bad, would that have been noticed on the bench test?

I just don't understand why the car dies during the afternoon. I can drive to work fine...but when I shut it off in my driveway...it doesn't want to start afterward.

 

During the half hour ride to work, it acts as if the battery is dead. Car dies. First time I jumped it and made it home. Today it did it again. It would not restart then. After working 10 hours it fired right up and got me home. Battery light works, and alt. is putting out about 14.3 The battery voltage with the car off had been slowly dropping from 12.4 When I checked it just now it was free-falling through the 10v range. I pulled the key from the ignition and it climbed back up through the 11's. and is currently at 11.7 I know my ignition switch has issues, but is this what could kill it like a dead battery while driving? Help please. My only vehicle and work again tomorrow. Battery is only a year old btw. Thanks.

 

i would have your battery load tested. then go from there.

 

are you measuring that 14.3V alternator output at the battery terminals ? try probing the actual battery posts, not the clamp termianls around them, if you still see 14.3V, then you probably have a dead battery. if the voltage at the battery posts is different than the voltage at the terminals, you probably have a bad connection.