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Car was running and driving with no faults/no issues. I started it one morning in my shop and it ran for a couple mins then I reved it a little and it died. When I tried to start back the key would turn and all lights would come on like normal but it would not crank (motor would not turn). The dash is giving a ESP fault and the engine Fan is running. When I ran the codes the only ones that will not clear are P208F (M16/7 Recirculated air flap actuator) Faulty and P202e-8 M16/6 (Throttle valve actuator) Deflection of throttle valve (po120)
So I though the ECU was Bad so I sent it to EIS for repair. They said the voltage regulator was bad and also the communication something needed repair. When I got it back in the car no change. Still the same issues as before.
Current State;
-Turns on but no crank (engine will not turn)
-ESP notification on the dash
-Engine fan runs W/O
-P208F (M16/7 Recirculated air flap actuator) Faulty
-P202e-8 M16/6 (Throttle valve actuator) Deflection of throttle valve (po120)
Attempted repairs;
-Sent ECU for repair (no change)
-Checked fuses (no Issues)
-Checked starter relay (it is working, jumped the contacts and engine turns) no signal being sent to relay with key is turned
-Checked all wiring for the Throttle body, didn't see any issues.
Question;
-Would the Two faults keep the car from trying to start?
-Is the ECU bad?
"Advance search" in W211 AMG subforum and with my user name will turn up a seriously long tech document about the CAN Bus in our cars. That will give you the location of the junction blocks and the topology of the network.
Last edited by bbirdwell; Jun 16, 2024 at 01:24 PM.
Thanks for the quick reply, I'll dig into the CANbus system. Would I be able to do the same type of test by scanning different modules until I found one that not connecting?
Thanks for the quick reply, I'll dig into the CANbus system. Would I be able to do the same type of test by scanning different modules until I found one that not connecting?
Yes, with caveats. If the can bus is non-functional due to a dead module you will not be able to talk to all of the modules of which one might be the one that is killing the can bus. If the can bus is non-functional, pull one connector at a time and see if the can bus becomes operational. If it does not become operational, reinsert that connector before you pull the next connector. Connector positions are tied to the electrical schematics. If you inadvertently swap two or more connectors into different positions it greatly complicates the troubleshooting process. I learned that lesson the hard way. If the can bus comes back online the connecter you pulled goes to the bad module. You should then be able to hook up a diagnostic tool and be able to talk with all modules except for the one that you disconnected. I used to be very apprehensive about working on a can bus but after several times working on it, I find it is not nearly as difficult as I feared.
I pulled the drivers side canbus and disconnected one by one. Still no start. Are there other canbus locations?
Would the two codes listed above cause a no crank? The ESP warning and the Fan running full blast make me think it's a ECU issue. Did your engine fan run when the TCU was bad?
Did you attempt to scan for bad modules using a good diagnostic system? Those often will tell you if there is an issue with the CAN bus. May or may not identify the module. On my W210 Xentry and an iCarSoft system both indicated a problem with the interior CAN bus but neither could communicate with multiple modules so I could not identify the bad module until I tested the CAN bus voltages while disconnecting one module at a time.
Remember, a bad module may not necessarily kill the CAN bus. The issue could be a bad module not responding or it could be a bad module killing communications across the entire bus. So, scan for bad module, then scan for bus operation.
Multimeter or CAN Bus analyzer are just tools used in conjunction with a good diagnostic system to identify the problem item.
FWIW, up til now I've used Xentry and a multimeter. I ordered a WOYO PL007 CAN Bus Analyzer but have not had a chance to use it (although I would prefer if I never have to use it).
Out of curiosity, have you ever worked on the throttle body? The two connectors for the two stepper motors are identical and others have swapped them by mistake. This is where a diagnostic system that can activate individual motors is handy to have.
I'm using a Autel System that can access modules. The upper TB had been disconnected for a vacuum leak and the car was started/ran after the repair.
I'll dig into the modules this week but I'm still not 100% sure the company I sent the ECU to fixed the unit. I had to send it twice because the first time I got it back the car would not recognize the ECU.
I got the ECU back for the third time and I still have the ESP notification, Fan runs on High, No Crank.
-I checked the CanBus in the drivers side floor and the network is communicating (I watched BBirdwells video and used the WOGO CANBUS decoder)
-I pulled the front SAM and checked for corrosion, it looked clean.
-I pulled the central gateway module (drivers kick panel) and checked for corrosion, no issues
When I pull codes I get;
-(CAN time out) on the TCM and A/C module
-ESP Module (CAN not communicating to the ECU)
-ECM Module (only two throttle body codes saying the TBs are imposable)
I got the ECU back for the third time and I still have the ESP notification, Fan runs on High, No Crank.
-I checked the CanBus in the drivers side floor and the network is communicating (I watched BBirdwells video and used the WOGO CANBUS decoder)
-I pulled the front SAM and checked for corrosion, it looked clean.
-I pulled the central gateway module (drivers kick panel) and checked for corrosion, no issues
When I pull codes I get;
-(CAN time out) on the TCM and A/C module
-ESP Module (CAN not communicating to the ECU)
-ECM Module (only two throttle body codes saying the TBs are imposable)
What's next?????
Looks like you have possibly three modules (TCM, A/C, ESP) that may not be functioning properly and not communicating on the network. One bad module not talking properly on the netwrok can bring everything to a halt. At the Can Bus, located at the driver's seat, disconnect (mark it and where it is to be replaced) once at a time to see if the car will crank. In each case the car shuld be off remove the can connector for one of the modules, turn key on and then see if it will crank. Any disconnected module that allows the car to crank is likely your problem with no crank. That module will likely have to be replaced.
I just checked the Can Bus rail in the drivers side. I unplugged 1 at a time and cycled the key waiting 60secs. Still no crank.
I used the WOYO PL007 CAN BUS Analyzer and the network was communicating.
I still suspect of the ECU. I checked voltage on the ECU, plug 1 (pin3 and 6 ) were only showing 3.8v. Can someone send me a ECM pin diagram with voltages?
Can c is not on-line.
I unplugged the module at the bottom with three wires (1is brown) and the network is communicating. But the car still won’t start. I think the 3 wire plug goes to the central Gateway, is this correct?
I still have low voltage coming out of plug 1 (pin 3&6) on the ECU. I’ll call sia electronics Monday and ask if they have the voltage targets.
I’ve checked every canbus rail. The only thing that makes the CAN network Communicate is when I unplug the one in the picture below, it’s located on the driver side floorboard. Can someone please tell me what this goes to?
I’ve checked every canbus rail. The only thing that makes the CAN network Communicate is when I unplug the one in the picture below, it’s located on the driver side floorboard. Can someone please tell me what this goes to?
Is this connection X30/5? Is there numbering of the connection ports? Schematic shows the X30/5 as having 11 connection ports but your picture shows 7. MB documents show X30/5 as the CAN connection at the left front seat floorboard.
The color of the wires indicate it is the CAN C junction block X30/5.
@Cookeville post your VIN and I'll pull up the WIS schematic for your car and provide you a list of which connection goes where. The VIN is important as it "should" provide the build configuration for your car.
The color of the wires indicate it is the CAN C junction block X30/5.
@Cookeville post your VIN and I'll pull up the WIS schematic for your car and provide you a list of which connection goes where. The VIN is important as it "should" provide the build configuration for your car.
Barry - I have the X30/5 printed for the X30/5 Schematic. I hesitated to post it if it wasn't the correct block. I have identified all the connections to the block. See attached.
Thank you, machild! That helps. Eleven connectors in the file you attached, only seven in the OP's photo.
I'm thinking if we discount #11, #10, #8, and #6, we might be getting close to the OP's photo. I can see the car operating normally without those four items but all of the others are critical functions. If so, #1 connector might be the ESP module N47 located next to the front SAM. Or, if the photo is backwards, could be the gear selector. Which end of the junction block is #1?
Now would be the time to run a "quick scan" and see what is the only module not reporting status. If so, we might have assisted in locating the issue.
That last attachment is great!!!! Looks like when I unplug the central gateway (N93) my X30 CAN signal is communicating. I'm going to try and run a test plug from the X30 to the N93 tonight, I may have a short.
Using the VIN, here's what I found (sorry for no screen grabs) For connector X30/5.
#1 - N47-5 ESP module
#2 - N3/10 ME-SFI Control Unit
#3 - Green and Green/White to N93 Central Gateway; Brown wire to ground
#4 - U527 (valid for electronic transmission) N15/3 ETC [EGS] control unit
#5 - U502 (valid for Airmatic) Airmatic with ADS control unit
#6 - valid through 05/2004 N63/1 DTR control unit
#7 - via splices connects to N80 Steering Column module, A1 Instrument Cluster, and N73 EIS Control unit
#8 - no connect
#9 - N15/5 Electronic Selector Lever module
#10 - N71 Headlamp Range Adjustment control module
#11 - U775 (valid for reversible emergency tensioning retractor) on and after 06/2006 A76/1 Right Front Reversible Emergency Tensioner
Looking at the photo, definitely the CGW connector but in a different location.
Last edited by bbirdwell; Jul 10, 2024 at 04:22 PM.
BBirdwell thank you. I'm going to try several things tonight;
-Check the incoming N93 for CAN Signal
-Check the N93 ground
-Run a test circuit from the X30/5 to the Central Gateway bypassing wiring (I have spare connectors)
-Swap CAN C box (I have a spare)
-Check the incoming CAN signals to the Central Gateway
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E55 No Crank
Which end of the junction block is #1? 
