Hi everyone I currently own a 1991 190e 2.3L witch as an alternator problem...

I started having problem with the car few weeks ago when the car would just die in traffic or at a stop!!! No problem changed the battery for a brand new 850cca and the alternator for a rebuilt 70amp unit. Ran fine for 3 weeks did not tested annything. Than BANG once again the car started to die again so I took the car to my local repair shop (the car needed an allignement annyway) and ask him to check the charging system. New alternator was fitted in... Than BANG the car just died once again but this time I had a voltmeter pluged in @ 10V!!!! So i started to test electric system. Found out with my clamp meter that the total amp cosumption of the car with normal heating engine running headlights on etc etc was about 60amps while the alternator is only putting 40 amps on idle (witch is 750rpm in drive)!!!! tested every system one by one;

Heater blower @ maximum power = +-16 amps
Fuel pump = 7.9 amps
low beam = 9.8 amps
parking light plus dash light etc = +-11 amps
+ other system witch I didn't tested equal 60+ amps

OVP relay was check fine
Battery was tested good
All the wire harnest from the battery to the alternator are at 0.2ohm
and finaly the 12V from the ignition to excite the alternator is alive

after all the testing ran the car for 2 days and then blew the alternator (probably the regulator witch leave me a reading of openned circuits on both side)

Can somebody help me I'm in great need of help

Thanks Pascal

 

Pascal did you end up solving that problem? As I have the exact same issue.