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Feelstranger 09-20-2006 01:16 PM

Dash indicator lights always on...
So, when I got this car (300d), there were indicator lights on all the time, and the fuel gauge was always pegged.
I fixed a burned through ground on the circuit board and everything worked correctly again.
Months later, i now have a problem where the fuel reserve light, brake light, alternator light and the brake pad warning light all stay on. Coincidentally, I recently discovered that the alternator must have not been charging since the battery was getting weaker and weaker at turning it over. I fiddled around with things and it seems that the alt charges with increased rpms - though the volts *slowly* climb - over maybe 20 seconds to around 14, I think.
Also, when I drive, as the rpms climb, the indicator lights mentioned above all get a little dimmer - sometimes almost out!
I checked the circuit board again and could find no broken paths, including the previous repair.
I'm stumped!
Could the Alt light be on legitimately, but voltage spilling over to the other light circuits?
Any thoughts appreciated!

in Vermont

Craig 09-20-2006 01:23 PM

It sounds like you have an alternator (more likely voltage regulator) or battery issue. It shouldn't take the voltage that long to reach it's normal levels. I have had strange behavior from the dash light due to a bad voltage regulator in the past. I bet the dash lights will fix themselves if you fix the charging issues.

Feelstranger 09-20-2006 01:35 PM

I wonder. I just replaced the brush pack on the alt last year!
Perhaps its faulty?

Craig 09-20-2006 01:37 PM


Originally Posted by Feelstranger (Post 1282157)
I wonder. I just replaced the brush pack on the alt last year!
Perhaps its faulty?

That's possible, also check all the connections. It could also be the alternator itself.

Feelstranger 09-21-2006 05:57 PM

A few questions...
I switched back to the old voltage regulator and the voltage still only creeps up as the throttle is held open...
Can you test the output of the alt directly - ie at the plug on the back - to eliminate other connection issues? Which wire would be the one to test of the two in the plug?
I tried both and the voltage still only creeps up - is this a valid test of the alt output?
I can't seem to locate any other connections to clean besides the ground strap on the fender wall -
Where does the alt output wire(s) run once they enter that wire conduit?

Feelstranger 09-22-2006 11:12 AM

My this board is busy these days...
Posts getting burried pages back in hours...
Anyone have answers to any of these ?

Craig 09-22-2006 09:36 PM

Just a few thoughts. It may be useful to get a battery/alternator test done. Places like Autozone normally do them free. That may help narrow down if it's the battery or the charging system. The connections I can think of are both battery connections, the negative battery connection to the fender, the connections to the starter, the connections on the alternator, and the ground strap from the engine to the chassis (one way to check that is to use a jumper cable between the negative battery connection and the engine block.

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