1987 Mercedes Benz 190e Battery Drains When Running, Charge

1987 MERCEDES BENZ 190E
150,000 MILES • 4 CYL • 2WD • AUTOMATIC
Avatar
COPPRTOP99
  • MEMBER
  • 2 POSTS
Scenario: Battery seems to be discharged when headlights are on. Anti-lock Light comes on, which to my understanding means less than 10v output. Car then slowly dies, battery dead. Have had two replacement batteries. Charge systems checks show everything fine. No erratic electrical behaviors. When low, turning lights on causes RPM gauge to rise even though the engine is idling and it's RPM in fact is not changing!

Any ideas? Possible weak spots like harness? Btw, it does not like to start in cold weather, runs very rough until it warms up. Then it purrs. I had a major-major done within the last 12 months (under 7000 miles ago).

Thanks!
Dec 17, 2007 at 11:55 AM
Advertisement
Avatar
RASMATAZ
  • ✓ASE Certified Mechanic
  • 75,992 POSTS
  • ASE Certified Mechanic
Any ideas? Possible weak spots like harness? Btw, it does not like to start in cold weather, runs very rough until it warms up. Then it purrs. I had a major-major done within the last 12 months (under 7000 miles ago).

When you turn key to On position do you see the charge light come on? Could be an open/loose wire, or the alternator is not putting out-get it load tested to confirm its outputs.
Dec 17, 2007 at 2:31 PM
Avatar
COPPRTOP99
  • MEMBER
  • 2 POSTS
[quote:dc6ecaa4b1="rasmataz"]hin the last 12 months (under 7000 miles ago).

When you turn key to On position do you see the charge light come on? Could be an open/loose wire, or the alternator is not putting out-get it load tested to confirm its outputs.[/quote:dc6ecaa4b1]


All lights were per user manual when key is at 'On'. Load test was supposedly done by my repair shop. Today they are trying to locate what might be draining the battery (????).

I'm having the vapors thinking these guys may not be electrical whizzes, although they've done all mechanical repairs right on.

I agree, the thing has to do with load... now, to find out what thing :-(
Dec 17, 2007 at 2:49 PM
Avatar
RASMATAZ
  • ✓ASE Certified Mechanic
  • 75,992 POSTS
  • ASE Certified Mechanic
Why don't you ask them what exactly does it mean to full field the winding in the alternator. If they don't know go somewhere else-
Dec 17, 2007 at 3:29 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.