Interesting. Do you know if the MB HHT (Hand-Held-Tester) was initially used or something else?

Also, was the PC-unit the official MB STAR PC Diagnostic system, or some aftermarket unit?

Again, congrats, and knock, knock . . .

:-) neil
1988 360TE AMG
1993 500E

Great!
 

I'm sure you're glad that it's fixed!

Note that the #6 code showed the real fault but ". . it got lost in the clutter". The 'live' feature of some scannrers is nice to have when this type of failure occurs but it was diagnosed without it.

Anyway, enjoy that great car!

Placo1, what I learned is that there are more than a dozen inputs that can cause the car to go into 'limp home' mode, and the diagnosis is difficult - part experience and persistence on the part of the techs, and part best available tools. So I don't feel confident that something else won't fail! I'm just more prepared to deal with it.

Neil, I do believe the first tool was the HHT. It was small and housed in yellow plastic, like a Fluke meter but fatter, if I remember correctly. I don't know the manufacturer of either unit. I'll ask.

JimF, the paperwork from last week's session reads in part (1 of 6 error codes still present last week): "CODE FROM D. M. DIAGNOSTIC MODULE PIN 19 - CODE 6: Idle speed control incorrect, fault from EA/CC/ISC" So only after I reminded Marty and my tech that the idle contact switch and the EACM (EA/CC/ISC module) had already been replaced did it lead further to the real culprit. They still wanted to replace the idle contact switch again. I'm interested in your comments on this.

Of side interest to JimF - one of the other error codes: "CODES FROM LH DIAGNOSTIC MODULE PIN 4 CODE 3: Engine coolant temperature sensor short or open circuit." I assume that's the added resistor keeping my engine cool, right? ;{) Without it, I would have been frantic with the amount of time the car sat there idling through all this exercise!

Also, I might add, that only because the part degenerated enough over the last several months that you could pretty much cause the event to happen every time you ran the car, could it be found "live". So I don't feel like anyone wasn't doing their job! But it was my tech's persistence that I credit with solving the problem.

Thanks again Mark.

When you ask about the HHT or HHT equivalent, also ask about the PC/Laptop used.

I heard MB is selling their STAR Diagnosis System supposedly only for IBM ThinkPad's at $20K/each, not including PC

:-) neil

Neil,

The handheld diagnostic unit used on my car is a Baum CS2000. The unit that Marty of LMV INFO brought in is the Mercedes STAR Diagnosis System.

Mark- that's good news. Is Marty of LMV INFO an independenet MB mechanic?

If so, where is he located. It's nice to know of an independent who has invested in some of the more esoteric tools.

:-) neil

As I understand it, Marty is a trainer/consultant, giving seminars and consulting with a network of member shops. He's a former MB tech.

B11/2 is the ECT sensor . .
 

but my CH affects the B10/8, CTS (Coolant Temp Sensor). My mod does NOT affect the LH-SFI in any manner. For backup info, please read the MS thread:

http://www.peachparts.com/shopforum/tech-help/16757-how-change-aux-fan-cut-point.html?highlight=CTS

DTC #3 is differentiated from DTC #2 in that #2 points to the one side of the sensor whereas #3 points to the other side of the sensor.

The resistance values for this sensor vs temperature are:

Temp(C)--Temp(F)-------- Ohms
20 --------- 68 ----------- 2500
30 --------- 86 ----------- 1700
40 ---------104 ----------- 1170
50 ---------122 ------------ 830
60 ---------140 ------------ 600
70 ---------158 ------------ 435
80 ---------176 ------------ 325
90 ---------194 ------------ 245
100 ------- 212 ------------ 185

Both sides should track each other and be within 5% of each other. If not, then it needs to be replaced. Glad the CH kept you car cool during extended idle time.

new thread: Intermittant 500E ASR problem
 

Rather than clutter this thread, I've started a new thread, "Intermittant 500E ASR problem" here:
http://www.peachparts.com/shopforum/tech-help/39898-intermittant-asr-problem-1993-500e.html

I'm giving notice here for better visibility.
In short, I only get it during startup (sometimes), and so far only during a cold start or when the car has been sitting for at least 4-hours. Yes it goes into Limp Mode. Disappears after a restart.

Please respond to the new thread:
http://www.peachparts.com/shopforum/showthread.php?threadid=39898

Thanks,
:-) neil
1988 360TE AMG
1993 500E

94 SL500 ASR/limp home mode
 

We have the same problem with 94 SL500 with 60K. A wiring harness was replaced and it still died. It wouldn't put off any code. Installed a new air flow sensor, but problem persists. Still no codes. Any advice appreciated. I'm brand new to this site and I'm not sure how to find all responses. I'm at FrancisDalton@aol.com and MaurAdler@aol.com

Thanks, Frank Dalton