90 300e Stall - No Crank - PeachParts Mercedes-Benz Forum

Jim_P · #1 01-30-2009, 12:41 PM

I'll keep it short and to the point. Slowed down to make a turn and car stalled. Attemped to restart but car acted like the battery was dead. I went back an hour or so later and car started right up. Went about 1/4 mi and car stalled again at a traffic light and just clicks when I turn the key. Normally I would spend the afternoon searching threads to find a solution, but a few quick searches aren't helping. It's 25* F here and the car is on the side of the road. It's a 1990 300e 2.6l. When I got it going the first time after it stalled the ABS and SRS lights were on, but car drove fine. Any help would be greatly appreciated.

-Thanks, Jim

Ferdman · #2 01-30-2009, 01:09 PM

Jim, I'd suspect two things: the voltage regulator brushes are worn down so far that the battey is not recharging properly, or the battery needs to be replaced. First, remove the voltage regulator from the back of the alternator and check the brushes. If they're worn down to nubs replace the voltage regulator. If that doesn't resolve the problem it's likely you need a new battery.

Jim_P · #3 01-30-2009, 01:19 PM

It doesn't seem that the battery is dead. When I restarted the car it cranked right over. I have another battery (same batt as my porsche). I'm looking at the wiring diagram at the moment. It appears the circuit goes from the battery through the ign sw - neutral sw- starter. I'll have to go and try again after work or tomorrow.

thanks for the replies.

tinypanzer · #4 01-30-2009, 05:20 PM

OVP Relay?

-tp

Cal Learner · #5 01-30-2009, 06:15 PM

Would a bad OVP keep it from starting?

Arthur Dalton · #6 01-30-2009, 06:25 PM

Nope.

Only on HFM/SFI is OVP power required for start ..[ b/c they are full electronic]

He has a low voltage condition and Ferdman is on the correct track..

Jim_P · #7 01-31-2009, 11:53 AM

Ok so it turns out battery was dead. When I went back lastnight to the car I tried starting it and I got the slow crank. I put in the other battery and it fired right up and I was able to get it home with not problems. I recharged the old battery on a 10 amp charger, then load tested it and it held good under load. Even retested it this morning again and it is still holding 11.5v or so under a load (hand held battery tester). I started the car and I am only getting 11.3v out of the alternator (with the new battery still in the car). Previously I had the imfamous pulsing lights (headlights and interior lights). I'm presuming the regulator gave up the ghost? Anyone have any thoughts on that before I order a new one? I'd rather not go for a rebuilt alt., does anyone sell a kit to rebuild these?

-Thanks again for the help,
Jim

Arthur Dalton · #8 01-31-2009, 12:05 PM

Pull the reg and see if the brushes are worn down...
Common wear item.

http://catalog.peachparts.com/ShopByVehicle.epc?q=1990-Mercedes--benz-300e--Base-Engine--Electrical&yearid=1990%40%401990&makeid=63%40%40MERCEDES%2DBENZ%40%4063%40%40MERCEDES%2DBENZ%40%40X&modelid=6194%40%40300E+Base&catid=240798%40%40Engine+Electrical&subcatid=240870@@Voltage+Regulator&mode=PA

dpkreuze · #9 02-02-2009, 01:00 PM

Friend,
Does the charge indicator lamp illuminate with the key on? The lamp is grounded through the alternator brushes. The ground potential is then canceled by alt. output to extinguish the lamp after start.
Brick