Hi guys, this is my first post on the forum. I am owner of W164 year 2010. Since some time when I start the car, climate control panel begines with manual settings, even if I leave the car on AUTO previus time. All functions of air con on the climate panel are available apart from rear window heating (it cannot be swiched on, only yellow diod is blinking when I press the button). After some minutes all diods on the climate control panel disappars but still buttons are working fine.

I checked with my diagnostic tool and found the following faults:

1. Multifunction (SAM - Front (Signal Acquisition and Control Module - Front ) -
SAMV164 (Signal Acquisition and Control Module - Front ) - MT/AT)
DTC Description
9043 - Terminal 30: undervoltage< 7 V
- Intermittent
90FF - Unknown fault code

2. Brake (ESP (Electronic Stability Program) - ESP164 (Electronic Stability
Program) - MT/AT)
DTC Description
6001 - The supply voltage of the control unit is too low (undervoltage).
- Intermittent

3. Climate (Climate control - KLA164 (Climate control ) - MT/AT)
DTC Description
900E - Terminal 30
- Low voltage
- Permanent

4. Multifunction (Steering column module - MRM164 (Steering column module) -
MT/AT)
DTC Description
9336 - Steering angle sensor; faulty signal
- Intermittent

5. Multifunction (Upper control panel - OBF164 (Upper control panel) - MT/AT)
DTC Description
9038 - Control unit faulty (Watchdog)
- Intermittent

So far I checked connection for all fuses that are responsible for that areas. No effect, still same faults. Battery is also in good condition.

Where is the common denominator of all the panels to avoid the undervolate issue?

 

How do you know your battery is in good condition? You may also have a charging or power regulation issue. The car's modules hate any undervoltage and they are very sensitive to it. Were there any other codes? What's your battery voltage engine on anf engine off?

 

I checked the battery in specialized battery service and they said that it is fine. The voltage is around 12.0V when engine is not running and with engine on 13.8V. So I believe this is not the battery issue. I also discussed with some guys and they said if there was a problem with battery the other modules would also suffer...

Here is the full last report:

Brake (ESP (Electronic Stability Program) - ESP164 (Electronic Stability
Program) - MT/AT) (after last fault code deletion)
DTC Description
6001 - The supply voltage of the control unit is too low (undervoltage).
- Intermittent

Brake (ESP (Electronic Stability Program) - ESP164 (Electronic Stability
Program) - MT/AT)
DTC Description
6001 - The supply voltage of the control unit is too low (undervoltage).
- Intermittent

Instrument (Assyst (Active Service System) - WIA164 (Active Service System) -
MT/AT)
DTC Description
No fault codes

Instrument (Assyst plus (Plus Active Service System) - WR164 (Plus Active
Service System) - MT/AT)
DTC Description
No fault codes
7F18 - Unknown fault code

Instrument (Instrument - KI164 (Instrument) - MT/AT)
DTC Description
No fault codes

Climate (Climate control - KLA164 (Climate control ) - MT/AT)
DTC Description
900E - Terminal 30
- Low voltage
- Permanent

Gearbox (Gear selector - Direct select control unit - AT)
DTC Description
No fault codes
U0168 - Control unit EZS is faulty
- no message
- Intermittent
Odometer
Main odometer reading: Last occurrence
Fault frequency first occurrence
Main odometer reading: First occurrence
Battery voltage, first occurrence
Servo module temperature, first occurrence
Servo module position. first occurence
Odometer reading at last occurance
Battery voltage, last occurrence
Servo module temperature, last occurrence
Servo module position. last occurrence
001
185392
0,00
-50
0,00
0
0,00
-50
0,00
U113B - CAN communication with Direct select control unit, faulty

Gearbox (Gearbox - 7G-Tronic (Gearbox) - AT)
DTC Description
No fault codes

Restraints (Airbag - Arcade (Airbag) - MT/AT)
DTC Description
No fault codes

Multifunction (Parking assistance - PTS164 (Parking assistance) - MT/AT)
DTC Description
9006 - Distance sensor, front left
- Connection has poor contact or the sensor or cable is faulty
- Intermittent

Multifunction (SAM - Front (Signal Acquisition and Control Module - Front ) -
SAMV164 (Signal Acquisition and Control Module - Front ) - MT/AT)
DTC Description
9043 - Terminal 30: undervoltage< 7 V
- Intermittent
9045 - Terminal 30: undervoltage< 7 V
- Intermittent
904B - EIS control module is not transmitting any data
- Intermittent
904C - Instrument cluster no longer transmits over interior CAN databus, CAN bus
OFF
- Intermittent
3438 - Unknown fault code

Multifunction (SAM - Rear (Signal Acquisition and Control Module - Rear) -
SAMH164 (Signal Acquisition and Control Module - Rear) - MT/AT)
DTC Description
C325 - No or incorrect CAN message from control unit Instrument cluster
- Intermittent
C331 - CAN communication with upper control panel; fault
- Intermittent
C335 - CAN; communication fault with control unit AAC pushbutton
- Intermittent

Multifunction (Steering column module - MRM164 (Steering column module) -
MT/AT)
DTC Description
9336 - Steering angle sensor; faulty signal
- Intermittent

Multifunction (Xenon headlamp (Xenon lamp) - Xenon lamp left - MT/AT)
DTC Description
No fault codes

 

Battery/alternator are good so now check grounds. I saw a similar post on the w211 forum and it was rusty grounds that were giving all the grief. There was an external one in particular inside the front fender lining that was exposed to moisture that was associated with the front SAM. Responses had great pictures of the ground location. Yes a different car but a good lead anyway. Hope this helps.

 

Thank you for the hint. While I was inspecting battery I notice some coffee under it. It could be from some years ago, perhaps previous owner. However the problem appeared a couple of week ago. As front SAM is located in similar area, I think it could be also affected somehow with the liquid.
Do you know where to check the ground in that area? I would also appreciate sending line to the thread you mentioned in your answer, as I could not find it.

 

Post your VIN - best to put it in your profile too, and I'll find the WIS documents that apply for your car. I'll see if I can find the thread as well.

 

VIN: WDC1641251A666399
Also added to my profile.
Many thanks for your help!!!

 

Here's the thread I was trying to recall. Its a different fault but indicative of how a ground can give you grief. An interesting read anyway. Sorry If I've given you the wrong solution. https://mbworld.org/forums/e-class-w...ml#post8915109

 

Here are the ground location point documents for the Front SAM. Look for ground point W15/1 in those documents. The first document is the most helpful. There is also a wiring diagram attached. Good luck

 

Many thanks! I will try to manage this week

 

I checked the gounds and cleaned just in case. All looks fine, chekcked with multimeter, there is good connection there. However, all sympthoms and fault codes remained unchanged.

 

I wish I could suggest a definitive way forward. One common item you have accross the list of codes is the Electronic ignition Module (EIS/EZS). Have you had problems starting it? Like inserting the key and you get ignition lights but no cranking of the engine? The EIS is a common failure and can be intermitent. Mine played up for about a month. Sometimes it was fine, other times took 10 minutes of turning they key to get it started.

 

Never experienced any problems with ignition. Engine starts always quick just after starter is applied.
I am now thinking if auxiliary small battery could not be a reason as I did not replace it from the very beginning. This could be maybe reason for the fault of the front SAM?

 

I worked some time and I managed to eliminate Front SAP undervoltage fault. There was coffee spilled around passenger seat and that went to areas where Front SAM is located. I took the SAM out cleaned with alcohol for electronics and now fault is gone.

Hovever, it looks that remaining faults are indepent from that. Climate control still does not keep the last settings (alwys starts with manual settings with A/C switched on) and after several minutes diods on the climate control panel stop working and I cannot turn on rear window heating.

Still have the following faults:

1. Brake (ESP (Electronic Stability Program) - ESP164 (Electronic Stability Program) - MT/AT) (after last fault code deletion)
6001 - The supply voltage of the control unit is too low (undervoltage).
- Intermittent

2. Climate (Climate control - KLA164 (Climate control ) - MT/AT) (after last fault code deletion)
900E - Terminal 30
- Low voltage
- Permanent

3. Multifunction (Upper control panel - OBF164 (Upper control panel) - MT/AT) DTC Description
9038 - Control unit faulty (Watchdog)
- Intermittent

Any idea how to go forward?

 

I replaced climate control module and all problems are gone.

 

Changing the Climate Contol module fixed your Braking/ESP codes or was it just multiple clearing of the error codes that sorted the ESP problem?

 

The ESP fault was not permanent. I think that was cleared once while erasing errors. I did not have any issues related to that fault.

 

2006 ML500, Front Seat Passenger VIN 4JGBB75E36A067142
Hi,
I found this post in search of solution to my issue. Wonder if you can help me. I have a stubborn SRS light. I've replaced some of the weight sensing parts not all. After I finish the seat adaptation with 16 kg and 45 kg, the scanner comes back saying there's an error code and it cannot complete the adaptation. The error code is 9A14, component WSS is incorrectly adjusted. The error comes from the Airbag module Arcade 164. I also pulled other codes related to passenger seat buckle, ignition circuit etc. Is this something you can help me with before I bore you with more error codes.
Thank you.

 

My errors were related only to undervoltage and defective climate control module which I finally replaced and after that the problem and errors disappeared.
I think your area is completely different, so I do not know how to fix as I am rather DIY not mechanic. Sorry but cannot help.