Questions and Answers

Mercedes Benz 190E Jump Start & Dies Q. Hi Vincent, I have a 1987 Mercedes Benz 190E 2.6 liter, automatic transmission with 160,000 miles on it. The car is fuel injected, has ABS brakes, P/S, A/C and cruise control. The problem with the car is as follows: the car will not start on its own, but if I jump start the car, it will start. My engine will run until I come to a stop, where the car will then die and will not start again until the car is jumped again.

The engine won't turn over or make any noise at all without being jumped. I had my alternator tested and it is charging as it should be. What could this be?

Thanks for your help!
Kevin

A. What you are describing to me sounds like a bad battery. I would assume if the alternator was tested, the battery would have been tested as well. Testing the alternator with a bad battery could give a false reading. I would have the complete charging system tested, especially the battery, again and I'm pretty sure you'll find the problem.

As an aside, the best way to charge a battery in a Mercedes is to take it out and slow charge it. Jump starting or charging the battery while it is connected often leads to electronics damage.

Another possibility is a defective Overvoltage Protection Relay (OPR) and Harness. The OPR protects the control unit(s) of various electronic systems, for example, CIS-E, ABS, etc. In case of a voltage overload occurring through the OPR, the electrical circuit is interrupted by the 10A relay fuse. So check that fuse to be sure it is good.