More 300D problems - PeachParts Mercedes-Benz Forum

stcbenz83 · #1 03-03-2007, 05:47 PM

I have a 84' 300D. Its out of service right now while i try to figure out the electrical gremlins. So after a week of sitting, i decied to start it up and let it run. (FYI. somthing is wrong with the electrical system so it wont charge, but i had enough battery left to start it) So before i start it while waiting for the GP to turn off. The brake pad wear senser is illuminated. THis is odd due to the fact that all the lights on the left side of the dash are not illuminating during pre-glow (part of the electrical problem) once started, the light continued to illuminate. The light never illuminated before the break down. Maybe a caliper is locked from sitting outside in the rain and snow?

So i decide to back it up and bring it forwards a couple times to maybe unlock the caliper. Well i end up getting stuck in my drive cause i havn't had a chance to get it plowed. So as im rocking the car, i lean out to look at the tire. and to my suprise it was not spining, only the passanger side tire was spinning. But when i put it in reveres the tire grabbed. Put it back in drive and the that side acted like it was dead. Is this normal?

This car has me so agrivated. mostly cause i only have time for one car, 2 is over whelming.

Just wanted to share. If you guys wanta put your $00.02 in, go for it.

#2 03-03-2007, 06:28 PM

Thank you for the warm welcome Bra,
Do you know how to check for a short in your elec. system?

stcbenz83 · #3 03-03-2007, 06:39 PM

Well i know mine is alternator related. TO check the electrical system theirs a number of different test you can do depending on what u need to find out out. Like for my GP system i used a charger and a copper pin to test each GP out and found that number 1 was compleltey shorted. For the alternator someone suggested taking the neg. battery cable off and if the lights were still on than the alternator is doing its job. the lights turned off, so thierfor i know its the alternator

sailor15015 · #4 03-03-2007, 06:40 PM

I think the tire thing is something to do with ours being a non-limited slip differential. When I got stuck in the snow, I only had one side spinning as well. Also, I don't know what you've done to search for your electrical problems but have you checked your battery to chassis and chassis to engine grounds, plus your voltage regulator? I ask because those gave me really crazy electrical problems on two different occasions, weird lights and wacky gauges and such.

stcbenz83 · #5 03-03-2007, 06:57 PM

Quote:

Originally Posted by sailor15015

I think the tire thing is something to do with ours being a non-limited slip differential. When I got stuck in the snow, I only had one side spinning as well. Also, I don't know what you've done to search for your electrical problems but have you checked your battery to chassis and chassis to engine grounds, plus your voltage regulator? I ask because those gave me really crazy electrical problems on two different occasions, weird lights and wacky gauges and such.

i hate that limited slip junk. It got me stuck even more heh. Umm the alternator is actully only like a month old. BUt i assume its bad because someone on here told me to try taking the Neg battery cable off and leaving the headlights on. If the light go out, the alternator is not doing its job, if they stay on, its supposedly ok. but who knows, its to cold to mess around with it now, So im stuck driving my 240D in the nasty snow and salt

psfred · #6 03-03-2007, 08:17 PM

Actually, that is one good way to fry a perfectly good alternator. There is a reason every shop manual says, in large letters, DO NOT OPERATE ALTERNATOR WITHOUT A BATTERY IN THE CIRCUIT. No battery, no voltage reference value, the regulator cannot control the alternator output voltage, and it will go overvoltage and pop the rectifier diodes. Dead alternator.

All you need is a voltmeter -- battery voltage with engine off and no major load is something like 12.5V. With the engine running, you must have at least 13.1V for the battery to charge. If you don't get at least 13.1V, the alternator is bad or the wiring to the alternator is bad and you have no power to the coil and it won't charge.

Peter

stcbenz83 · #7 03-17-2007, 05:37 PM

finally got to work on it, took the alternator back out (btw, much easier the second time around) took it to were i got it, and behold, the alternator went bad, yet agian. It was only charging at 10 i think? which would probebly explain why the light didnt go on, but yet the battery wasnt charging. ANyways, the new one is on order and should be here tomorrow free of charge of course. BUt since spring is getting here, i might just be driving the 300 Turbo for a week or so more, then she will be up for sale seeing as my 240D is my summer car.