PeterUbers

CerBErusM113

I wish I had some performance data to back up my impressions but I have found the TCU pedal reset does not yield as much perfomance on the M157 as it did on the M113k. However, a battery disconnect for 30 minutes has shown substantial improvement IMO. Shifts were crisper and 1st-3rd gear felt substantially more aggressive through the powerband. PeterUbers is there another TCU reset you are referring to or are those the two that you are utilizing as well?

PeterUbers

Stereolab42

I don't understand how this can work when there are three different mode settings C/S/S+, each of which already has preprogrammed shift patterns. Does this only reset the currently selected mode?

ShelbySteve

Can you do this with the push start in or does it need key plugged in?

mbmastertech

This "reset" is a huge myth. I've tried this countless times on many different models. Each time I've printed adaptation values in the trans and engine ECU's before and after i performed this reset procedure. Every time I compare the before/after values they are exactly the same. I've seen this being repeated all over on mbworld. I'm surprised no techs out there have said anything about this. I wish it did work. But it doesn't. I've tried it in every variation that's been stated online. Not once did it even change a single value.

chiromikey

CerBErusM113

Actually, on my m113k it was 2 minutes wait, on my m157 E it's been a 3 minute wait, I've noticed throttle response is different but the shifts are the same, when I pull the battery, I notice a change in shifts. Hope this helps a bit.

mbmastertech

Disconnecting the battery for a few minutes does reset adaptations in the engine ecu and the trans. The pedal trick literally doesn't do anything.

kponti

I believe this dance does not reset the TCU or ECU adaptations. I however think it sort of resets the TB adaptations (just a personal feeling, no evidence to back it up).

On my W211, I could reset the TB with a different series of song and dance and I did notice the results were similar to the so called TCU reset we are talking about here. On the M157, I have not seen this to be true, just crisper shifting with no real power increase.
I know the dance series has some truth to it at least on older models, I use it to reset Adblue adaptations on a few different MBs. And on those cars, you can actually see it change values.

For max boost under wot, I have seen that the car makes more power the 2nd and 3rd time you go wot on a dyno, regardless of setting or resetting. However after that reset, the only thing I see is the gears holding longer, not pulling harder.

I use the iCar OBD thing to reset ECU and TCU and I can definitely say that makes a difference. But once again, doing back to back runs makes a bigger difference than any reset.
Goes to show adaptations do their work well, but what you are putting in is the reasons adaptations go awry.

jvakos

Mbmastertech - so you only need to disconnect the battery for a few mins to reset the adaptations? and you only disconnect the main battery under the hood correct (not the trunk battery) to achieve this? will give that a shot. think i'm confusing this resetting trans adaptations with the "pedal dance" that worked on my old C32 AMG to make the throttle body wake up

NedNederlander

My W212 has been a bit 'jerky', it probably senses my moods.
After seeing this, I just tried the pedal dance in the garage before heading out for a 20mi trip... still jerky, the car.. not me.

5soko

I went over everything in WIS on resetting adaptions and trans resets... and came up with 0 on this gas pedal method of resetting anything On the MCT 722.9

PeterUbers

Cifdig

mbmastertech

10 minutes is plenty. I'm not sure about improving boost. Its possible.

PeterUbers

mbmastertech

​​​​​​Take the negative battery cable off. The battery is located in front of the passenger windshield area under the hood. There is a black plastic cover that latches onto the opening to the fresh air/blower motor area. Pop that off and you will see the battery.

Stereolab42

Alright, imma gonna do this battery removal thing tonight and report back tomorrow how it worked.

PeterUbers

Cifdig

Kei2thehwy

Ima try this, too... car has 42k on it before me, so it seems like a good idea.

thxrick

I'm in for results.

Kei2thehwy

I would ask if the auxiliary battery in the trunk powers the ECU for a short time. Of course I wouldn't want to disconnect both, possibly requiring the whole car to be reprogrammed, but I just wanted to ask that detail. Thanks.

PeterUbers