Mercedes-Benz Forum banner

'93 with strange electrical problems

1053 Views 6 Replies 3 Participants Last post by  redslk
Our 2.3 190E has started some strange electrical problems that we were wondering if anyone has any ideas.

Temperatures warmer here now, but noticed that the temp gauge gets hotter before the fan cuts on and the temp gauge seems to flicker, or bounce, alot. Also noticed that the speed of the windshield wipers have gotten much faster - yet we've changed nothing. The radiator cooling fan does cut on but sounds different than in the past.

Today, temps in the 90+, the car didn't overheat and the fan does cut on, but we now see that the battery appears to be boiling over. Sulfur smell from the hot battery and the water levels are down to about half of what they should be. (battery only about a year an a half old)

Will add water to the battery, and have an appt with service scheduled for the end of next week, but would really like to fix this sooner - an not on the road if possible! Anyone have any suggestions?? (Not sure that it has any relevance with this problem but we did have a severe lightening storm right before these changes started occurring, with a lightening strike nearby and lost our electric fence and VCR. Other vehicles adjacent to the 190 are fine.)

Barb
1 - 7 of 7 Posts

· Registered
350SLC, 500SLC, 300TE, 190E2.3 Sportline
Joined
·
687 Posts
Do not use the car!

You have described all the sypmtoms of a failed alternator regulator. The output of the alternator is not being controlled and is supplying excessive voltage and overcharging the battery. Not only will this destroy the battery, you risk destroying anything electronic in the car (including engine ECU and ignition system, cruise control, audio system, etc) burning out lamps and burning out the alternator. At the moment it is only the battery that is struggling to prevent the voltage from rising from the usual 14 volts to many tens of volts! Do not use the car until it is repaired. Chances are the fuse on the over-voltage protection relay will also have failed and will need replacement. Without this being done the car will run, but not well.
 

· Registered
2001 320
Joined
·
35 Posts
Discussion Starter · #3 ·
Thanks Greg! It's my husbands car and he was planning on taking the truck until we could ...

Thanks Greg! It's my husbands car and he was planning on taking the truck until we could get a better look at it.

So how hard is the repair? Something a fairly competent DIYSer can do?? If we can't repair, should we have the car towed in or do you think it will survive the 25 mi to the MB doctors??

Thanks again for the speedy reply!
 

· Registered
350SLC, 500SLC, 300TE, 190E2.3 Sportline
Joined
·
687 Posts
Alternator repair

Being a '93 it will probably have the later style alternator which is not intended to be serviceable. The repair is to simply replace the alternator with a new one. This is an easy job for a DIY type but unfortunately not cheap. If it happens to have the early series alternator, the regulator can be removed from the rear of the alternator and replaced with a new one. This is a less costly option if it has the early alternator (and it has sustained no other damage through the overcharging fault). If the car shows any signs of not running properly (inconsistent idle speed, difficult starting, etc) I would also check the fuse on the over-voltage protection relay (behind plastic cover behind battery). If you decide to have the workshop do the repair, I would be reluctant to drive the car 25 miles with the fault present.
 

· Registered
2002 SLK 32 AMG, bone stock. 1987 190E 2.3-16 valve (destroyed). 2005 E320 new toy.
Joined
·
14,798 Posts
Check the car out at R C Imports in Rockville. Rick belongs to the MBCA, and...

is very familiar with 190's. He'll do a good job cheap.
By the way, I have that hood insulation blanket for you if you still want it.
 

· Registered
2001 320
Joined
·
35 Posts
Discussion Starter · #6 ·
Yes!! I was wondering if you still had it available. Was actually thinking about sending...

Yes!! I was wondering if you still had it available. Was actually thinking about sending you a note today. Called Herb Gordon service and learned that they no longer have loaner cars available if the car is out of warranty - but they sold us 2 MB's now with the original agreement that we'd have free loaners whenever the cars came in for service for as long as we owned them!! Haven't spoken to our salesman yet but had an appointment scheduled for tomorrow and thought I better ask about a loaner. Didn't know if other HG customers were aware of this new policy. Looks like we'll be shopping elsewhere.

Planning to see how much voltage the alternator is putting out but we may end up trying the repair ourselves - thought about just replacing the alternator with a MB rebuilt one but understand that getting the belt back on may be a problem. Your suggestion of RC Imports may be a better idea than either HG or trying it ourselves!!

Barb
 

· Registered
2001 320
Joined
·
35 Posts
Discussion Starter · #7 ·
I think we have the later style alternator and would try to replace ourselves but understa...

I think we have the later style alternator and would try to replace ourselves but understand that getting the belt back on may present problems because it's spring loaded or something, suggestions???

The car starts right up and runs great but we'll also check the over-voltage protection relay fuse now that I know where it is!!

Thanks for all your help - we'd probably still be driving the car!! (actually I noticed that the headlights were not working now too - don't want to fry everything!!)

Barb
 
1 - 7 of 7 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top