560 SEL Fuel Pump Relay

[Tim Mabry]

My 87 560 SEL would not start today. The fuel pump isn't working. It will run when jumped with 12v. I suspect the fuel pump relay. Is this a common problem or could it be something more serious?

Fuel pump relay is a common failure. The test for the relay tests the inputs, not the relay. Easy to replace but not cheap. My 107 Euro has it located behind the glove box. Just remove the glove box light, then with a plastic wedge, remove the fasteners and pull out the glove box. It's a 5 minute job. Pull out and push in a new relay and you're done. Then, if it's not the relay... You might get an amp test on the fuel pump to make sure it's still good too. My $0.02 and worth it.

Steve
'85 SL500 Euro

[Benzmac]

The fuel pump relay in your car is located behind the firewall under the hood. It is common for it to fail. You should check the amperage of the pump(s). If it is higher than 8 or so, you should think of new one(s).

[Tim Mabry]

Thanks for your help. It was a bad pump relay. I took it apart and found a bad solder joint. I was able to resolder it and I'm back in business. I'll check the amps on the circuit ASAP. This is a very helpful sight. Keep up the good work. My next project is to get heat to the drivers side floor. Any suggestions?