Seat Control module - Lumbar support help
Thread Starter
Junior Member
Joined: May 2026
Posts: 20
Likes: 3
From: Scun~thorpe, North Lincolnshire
W212 E250 CDi 2015
Seat Control module - Lumbar support help
Hi,
The lumbar support control switches on my E250 CDI AMG premium night edition (both seats) are not working and having only just purchased the car, I do not know the history or when they stopped working.
So far I have checked all fuses, and all seat motions function from the door panels OK. I have tried new replacement genuine switches from a dealership and checked the wires are not damaged.
I have also used a diagnostic tool and performed the normalisation process.
I am now wondering if the Seat Control Module (ECU) is at fault. Part No. A172 900 69 03 - This appears to be a common module used throughout many models. Are these coded specifically to match the specification of a car, a particular seat or generic?
Has anyone got any experience on these modules?
Thanks,
Steve.
The lumbar support control switches on my E250 CDI AMG premium night edition (both seats) are not working and having only just purchased the car, I do not know the history or when they stopped working.
So far I have checked all fuses, and all seat motions function from the door panels OK. I have tried new replacement genuine switches from a dealership and checked the wires are not damaged.
I have also used a diagnostic tool and performed the normalisation process.
I am now wondering if the Seat Control Module (ECU) is at fault. Part No. A172 900 69 03 - This appears to be a common module used throughout many models. Are these coded specifically to match the specification of a car, a particular seat or generic?
Has anyone got any experience on these modules?
Thanks,
Steve.
Out Of Control!!
Joined: Apr 2019
Posts: 12,145
Likes: 6,881
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Hi,
The lumbar support control switches on my E250 CDI AMG premium night edition (both seats) are not working and having only just purchased the car, I do not know the history or when they stopped working.
So far I have checked all fuses, and all seat motions function from the door panels OK. I have tried new replacement genuine switches from a dealership and checked the wires are not damaged.
I have also used a diagnostic tool and performed the normalisation process.
I am now wondering if the Seat Control Module (ECU) is at fault. Part No. A172 900 69 03 - This appears to be a common module used throughout many models. Are these coded specifically to match the specification of a car, a particular seat or generic?
Has anyone got any experience on these modules?
Thanks,
Steve.
The lumbar support control switches on my E250 CDI AMG premium night edition (both seats) are not working and having only just purchased the car, I do not know the history or when they stopped working.
So far I have checked all fuses, and all seat motions function from the door panels OK. I have tried new replacement genuine switches from a dealership and checked the wires are not damaged.
I have also used a diagnostic tool and performed the normalisation process.
I am now wondering if the Seat Control Module (ECU) is at fault. Part No. A172 900 69 03 - This appears to be a common module used throughout many models. Are these coded specifically to match the specification of a car, a particular seat or generic?
Has anyone got any experience on these modules?
Thanks,
Steve.
The lumbar function usually suffer from pump and plastic fitting issues.
Can you hear your air pump running on command??
I have delt with seat modules, not lumbar yet.
Member
Joined: Apr 2017
Posts: 125
Likes: 69
From: Dallas, TX
2011 E350 4MATIC Wagon
Hi,
The lumbar support control switches on my E250 CDI AMG premium night edition (both seats) are not working and having only just purchased the car, I do not know the history or when they stopped working.
So far I have checked all fuses, and all seat motions function from the door panels OK. I have tried new replacement genuine switches from a dealership and checked the wires are not damaged.
I have also used a diagnostic tool and performed the normalisation process.
I am now wondering if the Seat Control Module (ECU) is at fault. Part No. A172 900 69 03 - This appears to be a common module used throughout many models. Are these coded specifically to match the specification of a car, a particular seat or generic?
Has anyone got any experience on these modules?
Thanks,
Steve.
The lumbar support control switches on my E250 CDI AMG premium night edition (both seats) are not working and having only just purchased the car, I do not know the history or when they stopped working.
So far I have checked all fuses, and all seat motions function from the door panels OK. I have tried new replacement genuine switches from a dealership and checked the wires are not damaged.
I have also used a diagnostic tool and performed the normalisation process.
I am now wondering if the Seat Control Module (ECU) is at fault. Part No. A172 900 69 03 - This appears to be a common module used throughout many models. Are these coded specifically to match the specification of a car, a particular seat or generic?
Has anyone got any experience on these modules?
Thanks,
Steve.
Thread Starter
Junior Member
Joined: May 2026
Posts: 20
Likes: 3
From: Scun~thorpe, North Lincolnshire
W212 E250 CDi 2015
The seat control module located underside are generally rugged to move seats reliably during collisions.
The lumbar function usually suffer from pump and plastic fitting issues.
Can you hear your air pump running on command??
I have delt with seat modules, not lumbar yet.
The lumbar function usually suffer from pump and plastic fitting issues.
Can you hear your air pump running on command??
I have delt with seat modules, not lumbar yet.
Thread Starter
Junior Member
Joined: May 2026
Posts: 20
Likes: 3
From: Scun~thorpe, North Lincolnshire
W212 E250 CDi 2015
Out Of Control!!
Joined: Apr 2019
Posts: 12,145
Likes: 6,881
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Thread Starter
Junior Member
Joined: May 2026
Posts: 20
Likes: 3
From: Scun~thorpe, North Lincolnshire
W212 E250 CDi 2015
Steve.
Trending Topics
Thread Starter
Junior Member
Joined: May 2026
Posts: 20
Likes: 3
From: Scun~thorpe, North Lincolnshire
W212 E250 CDi 2015
Having had a quick look on you tube, the back of the seats can be removed by prising off the back cover where the seat pockets are. Once this panel has been removed the lumbar cushion, module and pump are visible. Perhaps this could be my next option?
MB World Stories
The Best of Mercedes & AMG
Dubai Tuner Gives the Mercedes G-Class An Entirely New Look
Verdad Gallardo
Six Gift Ideas Your AMG Loving Dad or Grad Will Cherish
7 Craziest Things AMG Gas Ever Built
Verdad Gallardo
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know
Verdad Gallardo
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
MBWorld Fanatic!
Joined: Jun 2021
Posts: 3,176
Likes: 1,390
From: Fleriduh
W212 E63S Wagon - GSL580 - E63 - E350 - C300
There are two screws - then the rear cover goes UP to take it off. From there, there will be some hoses that are brittle and have holes. Easily replaced.
Thread Starter
Junior Member
Joined: May 2026
Posts: 20
Likes: 3
From: Scun~thorpe, North Lincolnshire
W212 E250 CDi 2015
MBWorld Fanatic!
Joined: Jun 2021
Posts: 3,176
Likes: 1,390
From: Fleriduh
W212 E63S Wagon - GSL580 - E63 - E350 - C300
Thread Starter
Junior Member
Joined: May 2026
Posts: 20
Likes: 3
From: Scun~thorpe, North Lincolnshire
W212 E250 CDi 2015
Hi,
That would be great. Would I be correct in saying that the control module, pump or both could be faulty?
If the tubes are corroded, surely the pump would make a noise, would it not? I have seen sellers selling the module, pump and cushion for approximately £40, used.
It sounds like this could be a simple job, if I have working components and good tubes.
Steve.
That would be great. Would I be correct in saying that the control module, pump or both could be faulty?
If the tubes are corroded, surely the pump would make a noise, would it not? I have seen sellers selling the module, pump and cushion for approximately £40, used.
It sounds like this could be a simple job, if I have working components and good tubes.
Steve.
MBWorld Fanatic!
Joined: Jun 2021
Posts: 3,176
Likes: 1,390
From: Fleriduh
W212 E63S Wagon - GSL580 - E63 - E350 - C300
In the GLS, yes...silent. the pumps are very well insulated. In every one of my experience the hoses went first. The E63 I had to put in a pump that lives behind the rear wheel
Thread Starter
Junior Member
Joined: May 2026
Posts: 20
Likes: 3
From: Scun~thorpe, North Lincolnshire
W212 E250 CDi 2015
S-O-L-V-E-D
SOLVED
I removed the back cover off the drivers seat and removed the power connector to the module, tested for 12v which was present and plugged it back in. All the pipes actually looked brand new!
I tested the switch and I could hear the pump running and all switch functions worked. I then did the same to the passenger seat and again all worked.
A big thank you to all of you that commented as this greatly helped me to find a solution.
Steve.
I removed the back cover off the drivers seat and removed the power connector to the module, tested for 12v which was present and plugged it back in. All the pipes actually looked brand new!
I tested the switch and I could hear the pump running and all switch functions worked. I then did the same to the passenger seat and again all worked.
A big thank you to all of you that commented as this greatly helped me to find a solution.
Steve.
Out Of Control!!
Joined: Apr 2019
Posts: 12,145
Likes: 6,881
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
SEAT electrical issues
SOLVED
I removed the back cover off the drivers seat and removed the power connector to the module, tested for 12v which was present and plugged it back in. All the pipes actually looked brand new!
I tested the switch and I could hear the pump running and all switch functions worked. I then did the same to the passenger seat and again all worked.
A big thank you to all of you that commented as this greatly helped me to find a solution.
Steve.
I removed the back cover off the drivers seat and removed the power connector to the module, tested for 12v which was present and plugged it back in. All the pipes actually looked brand new!
I tested the switch and I could hear the pump running and all switch functions worked. I then did the same to the passenger seat and again all worked.
A big thank you to all of you that commented as this greatly helped me to find a solution.
Steve.
What would your conclusions read ?
-- Your issue on both front seats were from two loose/oxidized connectors ?
-- Plastic Pipes & bladers were still fine.
BTW while we're here in summer... very similar fun with seat repairs ( oxidized connections + working on knees) there is cabin air filter !!
Take 15mn to replace your cabin filter before high current messes up your blower circuit with low air flow.
Last edited by CaliBenzDriver; Today at 04:02 PM.
