[NCC1701]

Several times over the past several weeks while driving my ESP Light has come steady on. Sometimes, but not consistently, while the light is on I have very slow pedal response from standstill up to 25-30 MPH or thereabouts.

In both cases, the light has eventually gone out on its own accord. And even while it's on the car sometimes seems to have a normal response.

What might the problem be? I'm a bit concerned this might be a worse problem in its early stages.

TIA

 

[jwight]

Any codes? Sounds like limp home mode - no idea why...

 

[Miss Mercedes]

I wonder if any reluctor rings are missing a tooth or are cracked? That would likely trip an esp fault.

 

[NCC1701]

I've checked for codes with ScanGaugeII and it shows no stored codes.

I don't know about the reluctor rings, nor how to check them (much less replace them). Hope that's not it. I thought reluctor rings were more of a problem up north due to winter conditions. If a tooth is missing, wouldn't the problem be more or less persistent?

I was hoping there might be clues in the facts that the symptoms are intermittent and that even while the ESP indicator is on the car mostly has normal acceleration.

 

[jimvw57]

A scangauge may not be able to read abs or esp faults I believe you will need a reader specifically for those systems

 

[NCC1701]

A scangauge may not be able to read abs or esp faults I believe you will need a reader specifically for those systems

Do you know of a device available for significantly less than an analysis from my local independent MB specialist? Or, is that visit likely my best bet?

<sigh> At least it isn't yet a driveability issue. What worries me is that it could become one.

 

[jimvw57]

Try your local auto parts store, most of them will read a code for free, they won't reset them but at least you will have the code. I have an Autel MS509 and it won't read ABS or ESP codes.

 

[NCC1701]

Try your local auto parts store, most of them will read a code for free, they won't reset them but at least you will have the code.

I'll try that as soon as possible. I had another episode today.

 

[Miss Mercedes]

I've checked for codes with ScanGaugeII and it shows no stored codes.

I don't know about the reluctor rings, nor how to check them (much less replace them). Hope that's not it. I thought reluctor rings were more of a problem up north due to winter conditions. If a tooth is missing, wouldn't the problem be more or less persistent?

I was hoping there might be clues in the facts that the symptoms are intermittent and that even while the ESP indicator is on the car mostly has normal acceleration.

I've been researching this issue for you, and I'm afraid there isn't a clear answer. I was surprised to find many threads on this issue and similar, each one with a different resolution. A forum search for "reluctor ring" brought up this one for me.

http://www.smartcarofamerica.com/forums/f353/yellow-triangle-abs-light-68450/

Looks like you're right on the northern aspect. Your reluctor rings should be fine assuming they haven't worn out in other ways, so I wonder if it has anything to do with the wheel sensors themselves?

 

[NCC1701]

New info on this issue: Got codes after my CEL came on, but the codes don't seem to relate to the engine. Maybe the accelerator position sensor?
P2138 & P2121
Pulled codes with ScanGauge, even though previously it showed no stored codes. My CEL hadn't previously been on either.

Armed with the codes, I found this old thread on SCoA:
http://www.smartcarofamerica.com/forums/f353/error-codes-p2121-p2138-37776/#post1107226

Found this part, A451-300-00-00
https://www.mbpartsexpress.com/oem-parts/smart-accelerator-pedal-mo-4513000000
$132 (plus s&h no doubt)

Again, I don't see the connection between a bad gas pedal and a CEL light.

Any thoughts, anyone?

 

[phillysmart]

I have had those codes recently (2008 smart cabrio 40k miles).

Dealer checked and found voltage slightly high, so replaced accelerator pedal assembly.

Two weeks later, codes came back. Dealer tried swapping new pedal and did not fix. Then they noticed my Area 451 cruise control and blamed it. Put in the jumper plug to take CC out of circuit and they claimed problem still existed and it was now a bad ECM (engine control module) that was "compromised" by the CC. BS. Wanted almost $1k for new ECM - told them no. No way that cc would hurt ECM. Probably loose wire someplace, will check myself.

Car seems to be working fine now, CC still jumpered out.

-Barry-

 

[Johannesl]

I have had those codes recently (2008 smart cabrio 40k miles).

Dealer checked and found voltage slightly high, so replaced accelerator pedal assembly.

Two weeks later, codes came back. Dealer tried swapping new pedal and did not fix. Then they noticed my Area 451 cruise control and blamed it. Put in the jumper plug to take CC out of circuit and they claimed problem still existed and it was now a bad ECM (engine control module) that was "compromised" by the CC. BS. Wanted almost $1k for new ECM - told them no. No way that cc would hurt ECM. Probably loose wire someplace, will check myself.

Car seems to be working fine now, CC still jumpered out.

-Barry-

I just went through something similar in my '13 with the gopedal. Was driving to work and ESP light lit up. Noticed no difference in the car so kept going. A couple miles later check engine light came on and car pulled power while I was in left lane at 80mph during AM rush hour.

I de-modded my smart (stock airbox back in and yanked the gopedal) for the 2 hour drive to dealership. They "checked" my car over and said it was the computer I have plugged into the obd port that caused all of this. I left my ultragauge plugged in when I dropped it off.

Haven't installed the gopedal again yet, but think that was the culprit all along. I kept it turned all the way up. Computer may have finally caught on.

 

[Rustedwrench]

New info on this issue: Got codes after my CEL came on, but the codes don't seem to relate to the engine. Maybe the accelerator position sensor?
P2138 & P2121
Pulled codes with ScanGauge, even though previously it showed no stored codes. My CEL hadn't previously been on either.

Armed with the codes, I found this old thread on SCoA:
http://www.smartcarofamerica.com/forums/f353/error-codes-p2121-p2138-37776/#post1107226

Found this part, A451-300-00-00
https://www.mbpartsexpress.com/oem-parts/smart-accelerator-pedal-mo-4513000000
$132 (plus s&h no doubt)

Again, I don't see the connection between a bad gas pedal and a CEL light.

Any thoughts, anyone?

The pedal has redundant position sensors that provide a input to the engine control unit. If a signal is erratic or the sensors do not agree, the control unit can not reliably control the electronic throttle body, thus the Check Engine light.