Hi all. I am a new to Volvo 240 wagon owner and discovered something strange today. To clarify I have a 1992 240 wagon.

While doing a few different things to the car to bring it back to 100% eletrically I removed the main gauges. Leaving them off all day and replacing all the little light bulbs. I turned the key on to listen to the radio, I thought no big deal I've done it before with no issue. Not even an hour later I decide to crank it up to recharge the battery. I get really slow turn over followed by nothing, no click of the starter or relay, just nothing. So I think ok I killed the battery, so I simply jump start it with another car and let it run for about 30 minutes. I turn it off and try to crank it again and the same thing, nothing.

Well I tried the old disconnect the negative battery cable trick. What do you know, the engine died. At this pint I pulled out the multimeter and started checking all the voltages. Everything was slowly dropping, battery and the volts off the alt itself.

Got to looking for a set of brushes and can't find any.

Then it hits me, I have a battery light that should come on. I plug in the main cluster and the engine instantly smooths out. No battery light either. Still having the multimeter hooked to the battery I go check the volts again. Very quickly mind you the volts were climbing. Let the car run for a bit then turned it off. Cranked it back up and it ran just fine.

Conclusion: Don't let your car run too long if you don't have your gauges in.


Sorry if this is already on here but I found nothing in my searching.

 

The alternator will not start charging unless the BAT light is ON in position II. Then it has to go off... Another way to get the alternator to "wake up" is to rev the engine over 2,500 RPM--easiest way.

 

interesting...

 

the alternator needs trickle current through the dashboard alternator light to the D+ terminal to 'jumpstart' itself. if the bulb is out or disconnected, the alternator can't start charging.

the circuit is, battery -> ignition switch -> alternator light -> D+

 

These European cars are so funny to work with. I would like the charging system would be pretty simple like normal cars. But nope always a good learning curve with this thing.

 

alternator lights work like that on most all non-computerized cars.