Permanently disable eco start by disconnecting battery cable?
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From: Wisconsin
2017 Mercedes E43 AMG, 2007 Lexus LS460 L, 2004 Lexus LS430
Permanently disable eco start by disconnecting battery cable?
So I pulled the battery from my E43, so I could run a power cable for an amplifier, and forgot to reconnect one of the two wires that attaches to that "distribution block" for the positive battery post. Now my eco start won't work ... which is fantastic. Nothing even happens when I press the button.
Can I just leave this wire disconnected or is it important for anything else? I haven't noticed anything else not working...
Can I just leave this wire disconnected or is it important for anything else? I haven't noticed anything else not working...
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2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
Reconnect the wire.
if you're curious, scan your car for soft codes/faults that have been generated due to that wire being unhooked.
if you're curious, scan your car for soft codes/faults that have been generated due to that wire being unhooked.
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So I pulled the battery from my E43, so I could run a power cable for an amplifier, and forgot to reconnect one of the two wires that attaches to that "distribution block" for the positive battery post. Now my eco start won't work ... which is fantastic. Nothing even happens when I press the button.
Can I just leave this wire disconnected or is it important for anything else? I haven't noticed anything else not working...
Can I just leave this wire disconnected or is it important for anything else? I haven't noticed anything else not working...
To OP, you disconnected the Hyundai battery sensor that reports the battery voltage back to the ECU, since the ECU cannot determine if it is safe to use the start/stop function (ie. low battery charge and with the risk of not being able to start again), it disables the start/stop.
If you really want to disable start/stop, there are scanners and of course one time use OBD modules to disable it or set as last known state.
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There are also other side effects, you might notice your engine rev higher as well. https://mbworld.org/forums/c-class-w...tart-stop.html
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To disable (or set as last known state for )auto start/stop with a scanner, here is one example that might work: https://mbworld.org/forums/e-class-w...ii-reader.html
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From: Colorado
G550
I ran my G550 for a couple years with this battery sensor disconnected and never noticed any problems. I coded the function permanently off after acquiring an OBD scanner with coding capability and reconnected the sensor.
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Thread Starter
Junior Member
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From: Wisconsin
2017 Mercedes E43 AMG, 2007 Lexus LS460 L, 2004 Lexus LS430
I also had two TCM codes which may be unrelated; U014800 - Implausible data were received from drivetrain and P060AC02 - Internal temperature sensor 2 of the control unit has a malfunction. There is a general signal fault. Hmmm. I'm actually at the dealership right now having an alignment performed and a software update for the drivetrain as there is an active recall relating to it. Perhaps these things are related? I will start scanning the car regularly to see if these codes come back.
There are also other side effects, you might notice your engine rev higher as well. https://mbworld.org/forums/c-class-w...tart-stop.html
To disable (or set as last known state for )auto start/stop with a scanner, here is one example that might work: https://mbworld.org/forums/e-class-w...ii-reader.html
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The main behaviour change is slightly higher idle and I guess the 12V battery is charged fully instead of the 80% (?) by default.
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I had several codes. Four were unrelated... low washer fluid, head unit losing network connection, air conditioning control unit which I had disconnected, and a code from disconnecting the light in the passenger footwell of all things lol. EZS (Electronic Ignition Lock Control Unit) had a couple codes relating to the battery sensor which makes sense.
I also had two TCM codes which may be unrelated; U014800 - Implausible data were received from drivetrain and P060AC02 - Internal temperature sensor 2 of the control unit has a malfunction. There is a general signal fault. Hmmm. I'm actually at the dealership right now having an alignment performed and a software update for the drivetrain as there is an active recall relating to it. Perhaps these things are related? I will start scanning the car regularly to see if these codes come back.
I also see from that thread that it can harm battery life. I'll leave it connected.
Yes, I've seen those. I might pick one up in the future. I wasn't really trying to disable the start/stop though. This was just a little accidental discovery.
I have an Alltel scanner. I don't have the model on hand. I'll do some research and see if it is possible to do so with it.
I also had two TCM codes which may be unrelated; U014800 - Implausible data were received from drivetrain and P060AC02 - Internal temperature sensor 2 of the control unit has a malfunction. There is a general signal fault. Hmmm. I'm actually at the dealership right now having an alignment performed and a software update for the drivetrain as there is an active recall relating to it. Perhaps these things are related? I will start scanning the car regularly to see if these codes come back.
I also see from that thread that it can harm battery life. I'll leave it connected.
Yes, I've seen those. I might pick one up in the future. I wasn't really trying to disable the start/stop though. This was just a little accidental discovery.
I have an Alltel scanner. I don't have the model on hand. I'll do some research and see if it is possible to do so with it.
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2023 E63S Wagon
I had to unplug that wire when I ran the lightweight lithium Antigravity battery so it would charge properly.
I never noticed the stop start thing because my tune already had it coded out!
EDIT: Oh wait I'm in the 213 section! My experience was from the 212 so YMMV and I edited out my "vote".
I never noticed the stop start thing because my tune already had it coded out!
EDIT: Oh wait I'm in the 213 section! My experience was from the 212 so YMMV and I edited out my "vote".
Last edited by I.T. Guy; May 30, 2025 at 09:29 PM.
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I had to unplug that wire when I ran the lightweight lithium Antigravity battery so it would charge properly.
I never noticed the stop start thing because my tune already had it coded out!
EDIT: Oh wait I'm in the 213 section! My experience was from the 212 so YMMV and I edited out my "vote".
I never noticed the stop start thing because my tune already had it coded out!
EDIT: Oh wait I'm in the 213 section! My experience was from the 212 so YMMV and I edited out my "vote".
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From: Canada
2023 E63S Wagon
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Got it so more sensors, more coding, more modules, more electrical fun I mean electrical gremlins.
