M-103: too many issues for the title... - PeachParts Mercedes-Benz Forum

400Eric · #1 12-31-2009, 11:49 PM

Can't find my amp meter. Haven't seen it since we moved. I'm gonna go out later and use the "spark method" in the dark. Works better that way.
Regards, Eric

gsxr · #2 01-01-2010, 11:11 AM

While I was mostly joking about the "spark" method... be very careful if you attempt this, as a spark near the battery can ignite hydrogen gasses from the battery vent. Wear eye protection and have water nearby, in case of an explosion (need to wash off the HCL acid ASAP). I know it's not likely, but you should be prepared just in case!

400Eric · #3 01-02-2010, 12:44 AM

Sorry it took me a while to report back....I had to wash the battery acid out of my eyes. Now you tell me!

(Just kidding). Some of the problem was traced to fuse "C", but most of the problem was traced to relay "A" (power seat relay). After pulling that, The fuse in "C" no longer sparked. One of "C"s functions is "control unit seat adjustment" so that would seem to be the common thread. No spark at battery now. So do I just replace that relay or do we have deeper issues here?

Also found a dead fuse in position "D", (auxiliary fan, at least that's what the inner lid label says. According to Uncle Stu's "Bible", I'm not supposed to have a fuse there till the 93 M.Y.!). Say, wasn't the aux. fan one of the things I was having trouble with? I need to peek in that fuse box more often! Still don't know for sure if that fixed the fan problem though cause it's cold now and the engine hasn't been exceeding about 80C which is too cold to engage the aux. fan. I guess I could turn the air cond. on to engage the aux. fan but I'm afraid to because the car is very low on freon right now. This is not so pressing right now anyway. I'll just keep a close eye on the temp gauge and tend to this issue (if needed) before the weather starts getting warm again.

I need to make this car reliable again. This is supposed to be the wife's car! I gave it to her because up until recently, it was the most reliable car I had ever owned. Now she's eying my latest acquisition: The 95 E420 (Benzer 4) that I haven't even put in my sig yet! We can't have that! "Bolbo 2" was being groomed to be her next car but I haven't had time to finish him.

Please read paragraph two again. Thoughts?
Regards, Eric

gsxr · #4 01-02-2010, 11:30 AM

Quote:

Originally Posted by 400Eric

Some of the problem was traced to fuse "C", but most of the problem was traced to relay "A" (power seat relay). After pulling that, The fuse in "C" no longer sparked. One of "C"s functions is "control unit seat adjustment" so that would seem to be the common thread. No spark at battery now. So do I just replace that relay or do we have deeper issues here?

Beats me - I'd just leave the relay out! Could be a bad power seat control unit (located in the seat frame itself, under the cushion, as seen here).

Quote:

Originally Posted by 400Eric

Also found a dead fuse in position "D", (auxiliary fan, at least that's what the inner lid label says. According to Uncle Stu's "Bible", I'm not supposed to have a fuse there till the 93 M.Y.!).

Please use a lower case "b" when referring to Stu's "bible". It has numerous errors, and cannot be taken as gospel - as you discovered. All non-V8 cars have a fuse in position D for the aux fan. Only 94-95 M119 V8 cars have cube relays with integrated GM-style fuses instead, located separate from the main fuse box. So yes, your car does need a good fuse in "D" position for the aux fan to operate.

Quote:

Originally Posted by 400Eric

I need to peek in that fuse box more often!

Um, yes. Yes, you do.

Quote:

Originally Posted by 400Eric

I guess I could turn the air cond. on to engage the aux. fan but I'm afraid to because the car is very low on freon right now.

If you read my previous post, you would know how to test it without running AC and without getting the car hot: ".... you can easily test this by shorting out the pigtails at the red or green switch at the AC drier behind the left headlight." This will turn the fan on low speed. If it doesn't run, check for +12v at the preresistor below the ABS pump. If voltage is present at only one side, the resistor is bad. If voltage is present at both sides, the fan itself is bad.

400Eric · #5 01-02-2010, 05:54 PM

Quote:

Originally Posted by gsxr

Beats me - I'd just leave the relay out! Could be a bad power seat control unit (located in the seat frame itself, under the cushion, as seen here).

Please use a lower case "b" when referring to Stu's "bible". It has numerous errors, and cannot be taken as gospel - as you discovered. All non-V8 cars have a fuse in position D for the aux fan. Only 94-95 M119 V8 cars have cube relays with integrated GM-style fuses instead, located separate from the main fuse box. So yes, your car does need a good fuse in "D" position for the aux fan to operate.

Um, yes. Yes, you do.

If you read my previous post, you would know how to test it without running AC and without getting the car hot: ".... you can easily test this by shorting out the pigtails at the red or green switch at the AC drier behind the left headlight." This will turn the fan on low speed. If it doesn't run, check for +12v at the preresistor below the ABS pump. If voltage is present at only one side, the resistor is bad. If voltage is present at both sides, the fan itself is bad.

The problem is I'm 6'3" 1/2 and the wife is 5'2" (or so she claims). I'm gonna have to address this seat issue sooner or later.

LOL! Yeah, that's why I always use the quotation marks when I refer to that book.

Yes, I did read your post, I always hang on every word

but I simply have too much to do right now....I know it's only a few minutes to do it but again, this might require the use of a meter which is still packed away somewhere. Plus I have to get B-3 ready for track day! It's OK though because it's hot today(!) and we have to run some errands so we'll have an answer on this by tonight.

Yes I have forgotten how to multi-quote. (Please don't be mad at me.)
Regards, Eric

gsxr · #6 01-02-2010, 07:22 PM

Quote:

Originally Posted by 400Eric

The problem is I'm 6'3" 1/2 and the wife is 5'2" (or so she claims). I'm gonna have to address this seat issue sooner or later.

I'd just have her drive one of the other 124's in your expanding fleet.

Quote:

Originally Posted by 400Eric

I know it's only a few minutes to do it but again, this might require the use of a meter which is still packed away somewhere.

Nope, no meter required for the basic test - short the switch leads (with the key on) and see if the fan comes to life. If it doesn't, then yeah, you'll need a volt meter, or at least a test light.

Quote:

Originally Posted by 400Eric

Yes I have forgotten how to multi-quote. (Please don't be mad at me.)

ROTFLMAO!!!!!!!

400Eric · #7 01-03-2010, 02:13 AM

What a C.F. today. Battery dead again. I left it hooked up overnight because I thought I had eliminated the "problem". I know this battery was good because when I was having the hard starting problem (because of the bad OVP fuse), I was cranking on that starter a lot and the battery would pull through. But now I'm wondering if I haven't deep cycled it one too many times or do I still have a drain somewhere? I'll try to find out tomorrow. (This battery is only a year and two months old BTW.) What made this day such a C.F. is my jumperbox's switch also went on the fritz today but I didn't know it. So I was chasing a problem with the car that had nothing to do with the car! (While the wife and kids waited impatiently buckled up inside the car!) Bunkness! While I was seaching I discovered the flat fuse/fuseable link thingy that lives on the strut tower in it's own little case right next to the strut mount on the D. side was bad. Is that also for the aux. fan? Anyway, in my desperation, I robbed the one from B-4 cause the one on B-2 turned out to be bad too! Great! Now I'm robbing parts from B-4! So that of course didn't make the car start but I'm sure it fixed something.

The only good news is the aux. fan is working now! Ya-frickin'-hoo!
Regards, Eric