Front SAM
10-21-2021, 06:21 PM
#1
Front SAM
Please advise. My 2011 E63 AMG with VIN last 8 digit BA428200 has a front SAM with part number 2129005011. When I checked with Mercedes Parts Center the latest part number corresponding to the year, model and VIN of my car is now 2319007707. The parts center included a complete list of replaced SAM modules. I observed that my part number 2129005011 is not included in this list. Does this mean that the part that is installed in my car is a wrong part? I am addressing this because I have a issue with my electric cooling fan running for no reason even when engine is cold. Hoping some experts reads this request. Thank you in advance.
10-22-2021, 08:35 AM
#3
I doubt a bad Sam would only have one symptom.
you need a scan for errors with xentry and I bet you'll find the fault. Likely a short in a temp sensor etcThere are a lot of different and updated part numbers for modules, I wouldn't get stuck on that
you need a scan for errors with xentry and I bet you'll find the fault. Likely a short in a temp sensor etcThere are a lot of different and updated part numbers for modules, I wouldn't get stuck on that
10-23-2021, 04:16 AM
#4
Front SAM
I went to MBEPC website. Furnished my VIN and I typed the part number of the SAM that is installed in my car 2129005011. The message came back UNKOWN. Maybe this SAM does not belong to my car?
11-23-2021, 05:29 PM
#6
Additional question diagnosing my cooling fan running even when engine is cold. There are four wires that connects to M4/7 plug that plugs into the cooling fan control module. One BN wire (ground), one RED wire (F32 constant 12V), one BKRD (From Front SAM) and GNBU (from ECU). When I disconnect the GNBU wire from the plug M4/7, the electric cooling fan still continue to run. However, when the BKRD wire is disconnected and the GNBU wire is reconnected the electric cooling fan stops running. Conclusion, is the Front SAM defective? Will appreciate your comments. Thank you
11-23-2021, 05:46 PM
#7
the BKRD is 12v ignition from sam only, the GNBU is signal from ECU, your fan is faulty or in second place your ecu is faulty which i doubt, change your fan.
edit: do you have fault codes in ecu like coolant temperature sensor or other related sensors that makes the ecu send signal to turn on the fan for safety?
edit: do you have fault codes in ecu like coolant temperature sensor or other related sensors that makes the ecu send signal to turn on the fan for safety?
Last edited by Robert AMG; 11-23-2021 at 05:50 PM.
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11-24-2021, 06:38 PM
#8
the BKRD is 12v ignition from sam only, the GNBU is signal from ECU, your fan is faulty or in second place your ecu is faulty which i doubt, change your fan.
edit: do you have fault codes in ecu like coolant temperature sensor or other related sensors that makes the ecu send signal to turn on the fan for safety?
edit: do you have fault codes in ecu like coolant temperature sensor or other related sensors that makes the ecu send signal to turn on the fan for safety?
11-25-2021, 04:52 AM
#9
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MY'14 W212 M276 3.5NA @60kMi
variable rpm smart fan
Thank you for your response. I have replaced the cooling fan with a brand new one and it still runs as soon as it is plugged in. There are no trouble codes or CEL. Why is it when the ignition wire (BKRD) is disconnected the fan stops running. But if the GNBU is disconnected while the BKRD is connected the fan runs. So the fan keeps running when the BKRD is connected even when the ignition switch if OFF. Completely a mystery for me. Thank you.
Super radiator Fan :
This engine fan is built for variable speeds controlled from slow all the way to supersonic.
The 100Amp power is translated in the need for a direct connection to the PreFuse main supply.
To put the fan logic to sleep, a gated ignition signal is toggled by the F-SAM.
The fan speed is remotely controlled by the ECU and communicated through a PWM signal.
Where this legacy design gets twisted is with the PWM duty cycle law:
- 0% duty for failsafe > Max speed!
- 10% duty is fan stopped.
- 100% duty is Max rpm
Overall it is somewhat confusing the first time you get introduced to various causes of Max fan speed:
- bad A/C pressure
- missing ECU PWM
- genuine Hi-Temp 100% cooling
Conditions that stop the fan :
- 10% PWM duty cycle from ECU
- Ignition off with delay from F-SAM
- (bad prefuse link, GND etc)
Smart Temp Gauge...:
While in the cooling Dpt, don't trust the InstCluster temp gauge, it's computer filtered to conceal the thermostat variable temperature setting, also computer controlled. The gauge purposely translates all that for a user friendly idiot-display.
F-SAM is ECU's butler:
My best tip to make friend with your "sleepless SAM'S" is to power cycle your battery bi-monthly. This will effectively reboot all your 40+ computers all at once.
Hope this helps with a happy Thanksgivings 🦃
Last edited by CaliBenzDriver; 11-25-2021 at 02:30 PM.
11-26-2021, 07:05 PM
#11
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MY'14 W212 M276 3.5NA @60kMi
Have a look at live data with a scanner.
You may want to unplug power to your fan if you think it's safe temperature wise such as Winter in Canada.
