New to me 190E 2.3 / Strange electrical issues. Need Help. - Benzworld.org

Insman · 12-28-2006, 08:56 AM

I just purchased my third W201. This one is a '91 2.3. It performs perfectly except for a few very strange electrical gremlins. This is one area of an automobile in which I am completely without competence.

When the ignition is completely switched off, the left side parking lights continue to burn. Playing with the switch causes some other strange things to happen such as firing the right front parking light but the lefts never go out. This is all still in the off position, btw. I'm thinking the switch is bad. I looked under there and saw the wires connected to the monster switch then travel somewhere together wrapped in cloth tape. Is there a simple plug hidden that would make it a simple replacement or do I have to take the individual wires off the old switch and put them "correctly" on a new one.

When cruising down the boulevard, sometimes the wind screen wiper likes to say hello. It will spontaneously go through its motion once or twice. I usually just wave back in amazement.

The third, and most comprehensive, issue is the pulsating lights. When the car is running, all lights constantly pulse from bright to dim. This includes the headlights. I'm thinking voltage regulator or the entire alternator but I don't have a clue where to start. It does keep the battery properly charged.

Could it be that all issues are related? I would love to replace a bad relay or voltage regulator or switch but I'm not so hot on tracing every wire looking for shorts and such. I'll do it if necessary but it will undoubtably require proper medication......lots of good, dark stout.

How about a bad ground. Could this be the culprit?

Obviously, I could use a lot of help. If you have any sparkling ideas or even random thoughts, put them out there. I like this little 2.3 and would like to get it in shape.

Thanks,

Sam

190Evoluzione · 12-28-2006, 09:03 AM

Your car sounds like a wondrous place to be, especially at night.
Welcome, and good luck with repairs!

'91 300CE · 12-28-2006, 02:36 PM

1st thing I would do is change every fuse in the car... they may look fine, but they are either broken or there are hairline fractures in the metal... my car was doing weird things when I got it, like door locks and alarm having minds of their own and the climate control clicked a lot.

Changing the fuses cleared it all up!!!

Insman · 12-29-2006, 06:10 AM

I just happen to have a baggie of fuses fresh from mailorder. I will replace as many as possible tonight. I will be a happy camper if this does the trick.

I've gotten advice to change out the headlight switch. Sounds like a winner to me as fiddling with it in the off position makes other lights come on or go off. Feels a little muddy in its action too.

The charging system is next.

Sam

**lomtevas** · 12-29-2006, 06:35 AM

Do you have any history on the car?

I remember seeing what you describe some years ago. There are car alarms that tie into the electrical system and allow for remote locking/unlocking and remote engine start. These alarms work all the lights and require direct connections to bus connectors.

What may have happened in your car is that such a system was installed and is now not used anymore. Its connections have gotten bad and the car's electrical system is suffering for it. Another scenario is that the previous owner removed that alarm system and in doing so, crossed up the wires.

Remember that these are suppositions, guesses and theories. Without a little more, this is the best I can do.

Insman · 12-29-2006, 08:04 AM

The car was owned by an older Gentleman who lives near me. The car is bone stock as far as I can tell. The service history is fairly good up until two years ago when he became ill and pretty much left the car inside a heated garage. Nothing was done during that time but it wasn't driven either. I seriously doubt it was even started.

Knowing this old fellow as well as I do, I can say with relative certainty that there is not, nor ever has there been any kind of aftermarket alarm on this car. His wife has a new Buick and he has strong words for the simple keyless entry fob on that car. "What's wrong with the damn key?" he spouts every time she presses the button. I think a proper alarm would drive him to absolute fits.

A few more things I ran across may help out somehow(don't know how, but maybe). The roller switch that determines when the throttle is closed, presumably to put things into idle mode, is never touched by the throttle arm. When I trip it manually the idle drops a tiny bit and is arguably smoother. The only way this could happen is if the Bowden cable is so far out of adjustment that it is restricting the throttle's range of motion. It shifts high and hard which I like but not at the expense of improper operation otherwise. I have two mint 2.6's that I can drive when I want cushy softness.

Many thanks for all of the suggestions. I will have more time tonight to smoke things over. I intend to have the charging system tested at O'Rileys, change out all the fuses including the OVP fuse, try adjusting the Bowden cable to free the throttle linkage, check to make sure the intake mani heater is not staying on all the time, and anything else I have time to tackle.

Any other specific things I should try before reporting back?

Sam

**lomtevas** · 12-29-2006, 06:54 PM

Then it's a pristine car.

Remove both kick panels under both sides of the dash and take a few digital photos and post them.

Also, under the hood next to the driver's side hood hinge, there is the fuse box. Remove the cover and take a photo of the fuses along with the blinker relay in the back, and post these pics.