No engine does not run. No crank, no start, only dash lights?

Yep, this happens when the radiator cooling fan has gone out. here are the wiring diagrams for the fan and fuse #54 so you can see how the system works and I have included how to change the fan assembly out. Check out the images (below). Please let us know if you need anything else to get the problem fixed.

Is there a test i can do maybe with a multimeter on the fan to make sure the control module is bad before i buy a new one ?

The fan has a simple power and ground connection which powers and grounds the motor, they vary the small ground wire to the module to control the fan speed. I would check the main ground and power and if okay replace the fan module/motor.

This guide can help and use the wiring diagrams above:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Please let us know how it goes.

I checked the ground and power wire and it’s good to fan. I ordered the fan. In the meantime, I disconnected both battery leads and ran a wire from positive lead to ground for a few hours. I read that I may reset the ECM and all control modules. When I reconnected the battery i got no crank anything. I connected my launch 3001 reader, and it said ECM. It’s a basic reader. Did i erase the ECM program when I grounded the positive lead? Maybe it doesn’t know the key anymore? What happened here? What can i do?

Also, I forgot to mention that when I turn the key the dash lights come on but then no crank no sound at all. I hope the ECM is still good.

Also, i jumper wire 3 and 5 on starter relay with key on position and engine cranks but no start. With relay back in key turned engine has no crank no sound. My reader now shows po607 code, control module performance.

I replaced the fan assembly and also the crankshaft position sensor. I still have no crank and no sound at all using key. I decided to jumper the fuel pump relay and starter relay with key in on position and it cranks but no start. I thought doing this would bypass the ECM and it should be starting. I’m not sure? After that I connected my 3001 reader, and it showed control module performance po 607 again but this time also camshaft sensors 1 and 2. I’m not sure if the sensors are bad or if the ECM is bad and not reading the sensors information? Can you read my previous replies to see what i did? What troubleshooting can i do next to get my car running again?

It sounds like you popped a fuse, I would use this guide and check all fuses I have also included the fuse locations.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

test the fuses with the system on. Check out the images (below). Please let us know what you find.

Checked all fuses one at a time and all good. Did a volt and ohms check on relays in engine compartment and checked good for starter, air pump, seq asg pump, term 15r, term15. Also checked in trunk the relays for fuel pump, term 15, term 15r. Also, good. I don’t know where the pre fuses are . I think where the battery jump connection is with the red cover. Are there some pre fuses there to check ?

With the key on do you have power at fuse #5 in the under-hood fuse panel and fuse #54 on the front sam control fuse panel? Here is the main power distribution. You may have popped the front SAM controller. Check out the images (below). Please let us know what happens.

Fuse 5 is in the trunk and my car does not come with that fuse, it’s empty. I check the power to fuse 54 under hood with key in second position and no volts. Is there a pre fuse that protects the front SAM that i can check? Also, how can I remove the SAM to check the circuit board? It looks like the wiper motor arm is in the way. Also how do I check the ECM? I heard they have problems with capacitors that go bad, and car will be dead. These parts are expensive, so I want to make sure it’s bad before I replace them. I want to do all the necessary troubleshooting first.

Hmm, it looks like the info is incorrect, fuse #5 is for the fan control module and fuse 6 should be 60 amp but by the image you provided the fuse is 20 amp? Is this a Euro car?

No, it’s not a Euro car. It’s called the Grand Edition model because it was the last year for clk350. I’m not sure if it’s a little different than the base model. I removed the front SAM and checked the circuit board, and it looks like new. Wiring and fuses all look good also. Part # is 2095452801. Part # of the ECM is A2721531092. Are there some prefuses that go to the front SAM? How can I check to see if it’s the ECM or the front SAM causing my no crank no start no sound?

This is the fuse chart that came with the car.

Okay, it this point we should run the codes for the CAN which will tell us if the SAM or PCM is not working. You can get a CAN scanner (Controller Area Network) which will work on most cars from Amazon.

Here is a video to show you how:

https://youtu.be/u-4syLc-ifQ


Please go over these guides and get back to us.

These are the codes i got using Launch 919x reader. Let me know if there are more checks i can do with this scanner to find problems. I would like to try the least expensive repair first that may fix my problem. I’m enclosing pictures of the screen codes.

You got some codes there :) The majority of them seem to point towards the bad engine control module. But I did see a code for the circuit 87 which feeds the controller. Does the engine run? If so, I would clear the codes and then turn the key on without starting the engine to see if any come up. Also, can you remove the front SAM control wiring connectors to see if there is any corrosion? Also, you might be able to open the unit up to see if it smells burnt.

No engine does not run. No crank, no start, only dash lights. With the key in start position no fuel pump sound or no starter clicking. The radiator fan still comes on high speed with key on and shuts off with key in off position. Replacing fan, I think was a waste of money. I checked the front SAM connector pins each one and circuit board and no corrosion. I opened ECM and board has no corrosion. I cleared all codes and then rescanned. I enclosed the pictures of codes. The ECM doesn’t show up in scan this time. When I tried to enter ECM in control units it showed communication error. Are there some checks i can do to see if ECM is sending signals to start car?

I don't see the images? also testing the ECM can be difficult I would remove it and send it in for evaluation. Here are the starter wiring diagrams so you can see how the system works.

Last scan pictures after clearing all codes and key in 2nd position. Is there anything i can do with my scanner to get the ECM to reset so the scanner can communicate with it?

Can you send me a diagram of the ignition switch to all the components involved in starting the car including the PCM signal? Also, do you have a troubleshooting chart from Mercedes that shows step by step what to check in a no crank no start to pinpoint the bad component?

Sure, here is the information you have requested. It still seems like the front SAM module to me. Check out the images (below). Please let us know what happens.

I ordered a used front SAM with same part number from a 2007 clk350 to avoid programming. I’m hoping it will be plug n play. Will take a few days to arrive. The wiring diagram you sent me I don’t see the wires from the ignition switch to the other components. I would like to see where the signal goes in the wiring in all three key positions. So, i can check voltage at components. Can you send me that?

yep, the ignition switch is the EIS control unit which I have provided above. Let me know what happens with the used front SAM module.

I installed the used front SAM and it started right up. It ran for 10 minutes, and RPMs stayed high at about 1,200 and didn’t come down. The radiator fan came on when reaching operating temperature. I turned engine off and connected scanner. It has a lot of codes. Not sure if they came with SAM. I didn’t clear any. I wanted to see what you say after reviewing them. I’m enclosing them here.

Yep, this could be because you stalled the SAM, I would clear them out and then turn the system on without starting the engine and then run the codes again, it does sound like we are getting closer to having the problem fixed.

I cleared the codes then rechecked with the key on. I have a lot of codes still. TCM, ESM, ESP, SRS, IC, AGW. Front and rear SAM shows good. SRS is showing on dash not operating. Also, radio shows on screen diagnosis and will not turn on. I’m enclosing codes.

Also, the ESP module in the engine bay is buzzing and ticking with key out. My battery is dead because of that using power. How can i fix that so it’s not running ? Is there a fuse i can pull in the meantime so it won’t kill my battery ? There is a lot of fuses for ESP so don’t know which one.

2 more codes plus 3 above.

Hi,

I noticed it has been a couple of days since we made contact with you. Have you been able to make any progress? I'm interested in knowing.

Joe

Did you have a chance to look at the codes above after replacing the sam ? I did not program the used sam just R & R. Not sure if i can use my launch 919x scanner to transfer program ? I have not tried to drive car with all those codes even though now it starts. The ESP is still buzzing and ticking using up my battery power. So I disconnected the battery for now. What is causing that ? What fuse can I remove in the meantime until it’s fixed ? Also radio is showing diagnosis on screen and will not come on. The SRS is showing inoperative on dash. What can i do next?

I haven’t received a reply to my problem in more than a week. I may have to start a new post.

I started the car today to do some checks. When the car reached normal temperature, the fan did not come on like before. It shut down and red coolant warning came on even though it was not overheating. I tried to restart, and it popped fuse #54 which was my problem before I replaced SAM. I replaced fuse and it started but shut down in a few seconds with coolant overheating light on. The A/C is off, so I don’t think it’s the A/C temperature pressure sensor. Should I try to disconnect the fan connector and A/C temperature sensor and start the car that way to see if it shuts down? Maybe it could be the PCM? I still need help to solve this.

Sorry for the delay, yes, I looked at the codes and it does seem like the PCM is out. Here is the location so you can send it out to be checked. Check out the images (below). Please let us know what happens.

Can you recommend a place to send out the PCM?

I use AER in Fullerton, California.

I called AER and they said they don’t work on Mercedes modules. Do you have another option?

Not off hand, I would do a Google search to see who could test it for you.

I sent out the PCM for testing and repair. I’ll let you know in a couple of weeks when I get it back if it fixes the problem.

Sounds good, have a good week.