P0685 relay circuit fault help?

[shawk11]

Hi, my car broke down last week and I took it to the mechanic he said that this message came up and he doesnt know what is wrong with it. It is a viano mercedes 2011, he cannot locate where the issue is so if someone could help me I would really appreciate it.

"The output for the relay 'circuit 87 (combustion engine)... there is a general fault."

 

[John Laidlaw]

That’s quite universal- Powertrain Control Module (PCM) isn’t getting voltage
Presume it stalled and wouldn’t start again?

 

[Steve@Avantgarde]

A bit more information on the cause of breakdown would be good.

What happens now? Does the engine crank over? Is the ignition dead?