w210 electrical issues, car dead - PeachParts Mercedes-Benz Forum

notfarnow · #1 02-06-2010, 11:19 AM

I'm having this trouble in my 99e300d, but I thought I'd post here just in case this is something someone had in their w210 e320 or e420.

Hopefully someone here will be able to help me wrap my head around this one. It's one of those things that could be something SIMPLE, but could just as easily be something BIG AND BAD

About 2 weeks ago, I started having these weird electrical issues:
- "clicker" for turn signal indicator wasn't "clicking", but turn signal worked fine
- indicator light for the right turn signal was dimly lit all the time, if the headlights lights were turned on
- If I had the high beams on, and used the turn signal, the speedometer would quit, and traction control & ABS would shut off.
- If I lock the car as soon as I get out (while the fog lights are on for 10-15 seconds) the alarm would go off. If I wait for the fog lights to turn off, the alarm DOESN'T go off.

Anyway, I've been just living with the issue, because this week I was going to be working on the car anyway to replace a couple glow plugs and change the oil. I figured I'd investigate and probably find a bad wire somewhere.

Skip to the other day:

Start getting the "low battery" light when starting the car. Battery is good, one year old, 950 CCA. But yeah, the car cranks slow. Car starts, I head home. 10 miles down the road, battery light comes on again, then ABS light, then power windows won't work.

I pull into my garage, and while it's running I test 10.5v at the positive post under the hood. I turn the car off and test 11.9v at the battery.

I figure I need an alternator (car has 210k miles) so I order one, put the car on the charger overnight. Next morning the car fires right up, but by the time I get to work the "Low Battery" warning is on. When I get back in the car an hour later, the car won't even crank over.

I come back into town with a fresh battery, drop it in and head home. By the tiem I get home, it's the same thing. "Low Battery" warning, power windows dead, ABS light on, and even stumbling a bit at idle. to back it into the garage, I have to go from drive, then neautral, then reverse *twice* before it actually goes into reverse.

So anyway, now my car is immobile in the garage. My questions is this... someone told me I could use toothpaste to buff the plastic headlight covers. Will that work?

Matt L · #2 02-06-2010, 11:54 AM

Skip the toothpaste except for oral hygiene. 3M sells a kit with sandpaper and polishing paste, and anytime that I hear it mentioned, the reports are positive.

I'd check for bad ground points for the electrical problems. Bad grounds can cause all sorts of trouble, and it appears that you might have a few of them.

notfarnow · #3 02-06-2010, 12:04 PM

Quote:

Originally Posted by Matt L

I'd check for bad ground points for the electrical problems. Bad grounds can cause all sorts of trouble, and it appears that you might have a few of them.

Where should I start my quest for bad grounds?

Matt L · #4 02-06-2010, 12:27 PM

Behind the instrument panel for sure. Also there is a ground point near the headlamp and side marker lamp, and that may cause trouble with the blinker. Then there's the big one between the engine and the body.

notfarnow · #5 02-06-2010, 12:31 PM

Quote:

Originally Posted by Matt L

Behind the instrument panel for sure. Also there is a ground point near the headlamp and side marker lamp, and that may cause trouble with the blinker. Then there's the big one between the engine and the body.

OK, I'll do a search to see how I get the instrument panel out. Yikes

thanks!

d.delano · #6 02-06-2010, 01:49 PM

If you can get to the alternator easily I'd check the voltage regulator on it. It's very likely to be totally shot and not doing the job. It's a $30 part and takes 5 minutes to replace. That should have been the first thing that came to your mind given the common occurrence that it is, now you're out the cost of a new battery and a new alternator.
Also, be really careful when you go trying to remove glow plugs on that car. Lots of people have had plugs break off and get stuck in the cylinder head due to the steel glow plug bodies siezing to the aluminum cylinder head threads. From what I've read it's almost a guaranteed trip to the machine shop. So don't just go tearing into it. If I were you I'd start soaking them with penetrating oil right now, and do it every day for a week then carefully try to remove them. When installing new plugs use copper antisieze paste on the threads. Good luck

notfarnow · #7 02-06-2010, 02:21 PM

Quote:

Originally Posted by d.delano

If you can get to the alternator easily I'd check the voltage regulator on it. It's very likely to be totally shot and not doing the job. It's a $30 part and takes 5 minutes to replace. That should have been the first thing that came to your mind given the common occurrence that it is, now you're out the cost of a new battery and a new alternator.

The battery was replaced last year because it was 10 yrs old and *beat*. I wanted an alternator anyway so I'd have a spare on hand, just like I do with starters and suspension parts. I'm a realtor and use this car *a lot*... I don't like waiting for parts. Appreciate the regulator idea... I didn't know they could be changed seperately

Quote:

Originally Posted by d.delano

Also, be really careful when you go trying to remove glow plugs on that car. Lots of people have had plugs break off and get stuck in the cylinder head due to the steel glow plug bodies siezing to the aluminum cylinder head threads. From what I've read it's almost a guaranteed trip to the machine shop. So don't just go tearing into it. If I were you I'd start soaking them with penetrating oil right now, and do it every day for a week then carefully try to remove them. When installing new plugs use copper antisieze paste on the threads. Good luck

Yep, been there done that.
http://jakesbenzconversion.blogspot.com/2008/02/glow-plug-disaster.html

Ever since that episode, I take the plugs out every year, ream the holes and anti-seize the plugs.

d.delano · #8 02-06-2010, 04:01 PM

Yikes. That's what I'd call an ordeal. Good recovery though! You had better luck than most. Those 99 turbodiesels are fine cars, worth a lotta dough. Have you had any problems with the front coil spring perches? Being from Montreal I'd be concerned about rust on the welds at those locations, and elsewhere about the car. Again, great save!

Ruination Fan · #9 02-06-2010, 06:27 PM

Have you tried a new K40 relay? It the relay/fuse panel under the plastic panel on the passenger side (where the 38 pin diag. connector is)....that is power supply relay for a lot of things related with the glow plugs and power distribution.

notfarnow · #10 02-06-2010, 07:07 PM

Quote:

Originally Posted by d.delano

Yikes. That's what I'd call an ordeal. Good recovery though! You had better luck than most. Those 99 turbodiesels are fine cars, worth a lotta dough. Have you had any problems with the front coil spring perches? Being from Montreal I'd be concerned about rust on the welds at those locations, and elsewhere about the car. Again, great save!

Actually this car came front Montreal, and I am fighting some rust issues. The spring perches were done before I bought it, but the rockers are soft in a couple spots, and there's a small hole in the trunk. The more I read, the more I'm thinking I'll have to check for rust in the battery compartment. Maybe there's a hole in there, causing moisture that's wreaking havock.