My E420 has been starting in limp home mode every morning when it's cold out, but there is no accompanying ASR light, as is usually the case in a limp-home scenario.

I can turn the engine off and restart and it won't give me any problems for the rest of the day. Any ideas? The ETA was rebuilt once a few years back, the wiring harness was replaced, and the brake and neutral safety switch were also just replaced. Is this a typical symptom of a failing ETA?

Thanks.

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles

Not likely. Does the ASR light come on with the key ON? And does it then go out when starting?

How strong is the battery? Have you checked the charging system?

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Emerydc8,
I thought I was the only one on the forum with this strange problem. I have been fighting it for 2 years with my '93 300CE. Look up my posts to see what I have replaced, all to no avail. The general consensus from MB Doc and other experts is that it is an electrical problem (but where?). We have practically taken the car down to nuts and bolts level and still haven't found it. My last great hope is that I have a retired Benz Master mechanic on it now. It has become a challenge to him.
Anziani
'93 300CE 204K
'95 E420 123K

Limp Home mode is a transmission problem not a stability system issue.

__________________
Good luck.






1998 E320 Wagon

Lucky you! Obviously you have never experienced it. It is a engine function that causes one to depress the pedal almost to the floor to get any power. The shift points are all messed up in that one has to lift off the pedal to get to the next gear. It is a safety function (why I don 't know)
If you have the answer you will make hundreds deliriously happy!
Anziani

The ASR light comes on and goes out during start as it should. I will probably start by hooking up a charger to the battery overnight to see if that is the issue.

This is strange because it doesn't leave me stranded--it's just troublesome because it shouldn't be doing this and perhaps it is a harbinger to an ETA failure or something more expensive.

RichardM98: The problem happens with the car sitting in park, before the transmission is even engaged.

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles

Richard, you're doing the wrong generation, this is a 124.

I'm skeptical about "rebuilt" ETAs. There's too many things they can't and don't actually rebuild. They rewire, they clean, and they test - and then they ship them out and hope for the best, which sometimes doesn't last too long. Are your codes confirming ASR issues?

I stand corrected as far as EC/CIS triggering a Limp Home mode.

Here is a list of all DTC codes for the W124 incase anyone needs it.

http://www.w124performance.com/docs/mb/diagnostics/DTC_List_W124_M104.pdf

__________________
Good luck.






1998 E320 Wagon

I pulled the codes:

Socket 6 (ABS/ASR Module): DTC 30 (CAN Data Line to EA/CC/ISC N4/1)

Socket7 (EA/CC/ISC Module): DTC 3 (EA/CC/ISC Actuator); DTC 6 (Starter Lockout)

Socket 19 (Diagnostic Module): DTC 6 (Idle Speed Control Inop)

I'm not sure what these are pointing to, but the limp home mode seems to occur just about every time I start a cold engine.

Any thoughts?

__________________
1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles

Was the starter lockout switch on the tranny adjusted properly during installation? Clear the DTC, if EA code 6 keeps coming back, your new switch either wasn't installed correctly, or is defective.

Otherwise, it's pretty likely to be a faulty ETA. If it was rebuilt once already, I'd say it's suspect. Strange that the ASR light doesn't trigger on the dash though. Less likely would be a flaky ASR or E-GAS module.

__________________
Dave
Boise, ID
Check out my website photos, documents, and movies!

I installed the Neutral Safety Switch and adjusted it as per the manual, using the alignment hole in the NSS arm and the body of the switch. I cleared all codes, so if I get the NSS back, I will suspect it is faulty out of the box.

After reading about the experiences of other forum members with ETA rebuilds, I have no faith in any company's ability to rebuild an ETA and have it work over the long term. Has anyone checked with the dealer to see what an MSRP would be on a brand new one (presuming they sell them)? I'm almost afraid to ask.

I'm going to put the battery on a charger tonight and see if it starts in limp mode in the morning.

__________________
1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles

It's around a thousand for your car, maybe a little less. I sent you a PM.

I believe gsxr is right-on with his explanation. You can check your ETA's operation by using Victor's video w/ an ohmmeter here

Hopefully you should get some clues as to what's wrong.

__________________
Regards . . . . JimF
-------------------
'94 S500 Cpe

Visit my Mercedes Web Page

Has the wiring harness been changed out?

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Jim

The wiring harness has already been replaced.

I left the car in the garage last night and kept it on a battery charger. It didn't go into limp home mode upon startup. I'm not sure if this was because the battery was charging all night or because the temperature here was only in the 50's outside and the garage was even warmer.

No codes appeared today.

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles