2018 GLS63 - U0401 Fault Code
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GLS63
2018 GLS63 - U0401 Fault Code
Hi - I'm new to the forum and this is my first post. I just completed a 4,000+ mile road trip with my '18 GLS63 and a 14' trailer in tow. During the course of my trip I experienced almost daily (1-2 times) a sudden loss of power. It would only happen for maybe 10-15 seconds where I'd be pressing on the throttle but with no throttle response or acceleration. Once I got home I connected my scanner and one of the codes I found was a U0401-00 code. From the limited research I've done it indicates a loss in communication between the ECM and PCM. When this occurs, one of the symptoms can be a loss of power (maybe the vehicle goes into a temporary 'limp mode' until communication is restored). I did not get a check engine light during any of these occurrences. Does anyone have any experience with what I've described. Any insight or advice would be much appreciated.
Out Of Control!!
Joined: Sep 2018
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2017 GLE350 4MATIC
Update? How is the vehicle? Did you have it scanned recently?
Loss of comms could be battery nearing end of life. These vehicles need 100% good batteries to function properly. The battery for this vehicle could be approaching 6+ years old depending on build date. I would replace the main and aux batteries.
Loss of comms could be battery nearing end of life. These vehicles need 100% good batteries to function properly. The battery for this vehicle could be approaching 6+ years old depending on build date. I would replace the main and aux batteries.
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Newbie
Joined: Oct 2023
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GLS63
Hi - Thanks for your comments. I replaced the battery a few weeks ago with OEM MB battery. I took it in to MB and have just confirmed that there was a turbo boost pressure sensor issue. I haven't gotten it back yet to confirm issue is gone. They said there was a code indicating a faulty boost pressure. That was odd because I don't recall seeing that code when I scanned it with my Snap On Solus Edge. I'll post again with more details as I get them,
