Mercedes Repair Questions? Ask a Mechanic for Answers ASAP
Hi Willie, are you checking fuse 28 for voltage when cranking the motor? If you have no voltage I'd try a new fuel pump relay.
The relay is located on the relay panel under the left side of the dash.
Click on the attachment below.
Have you checked your inputs to the relay? You should have power on pin 17 and 19 with the key on.
Will the car run if you bypass the fuel pump relay?
You will need to remove the relay and place a fused jumper lead from terminal 17 (power in) to terminal 20 and 23 (power out).
Ok, so it sounds like you have more than a fuel pump problem. The ECU energizes the fuel pump relay and initiates spark and fuel injection. Have you tested for spark and injector pulse? Will it run if you spray ether into the air intake?
Sounds like there is no power to the ECU or the ECU is bad. I'd start by checking for power at the ECU.
I'm not sure if those are the correct pins but if you have power and ground to the ECU and no spark, fuel pump or injector pulse you may have a bad ECU. Have you checked the timing belt to see if it broke? Checked compression?
Hi Willie, I'm out of the office until Monday. I will opt out for now and check back with you on Monday.