Our teams have dealt with a non-start situation with on many Mercedes commercial vehicles.
The main cause of the START ERROR being displayed on the dash is due to corruption of data in 2 of the vehicles main units,
one is the Temic immobiliser box also known as the WSP and the Main Engine control unit.
We recommend trying a few things before going deeep!
Test vehicle’s battery to be in a good state
Try a different key
Try the original key on its own with no other keys surrounding the ignition
If you have done this and you still have the START ERROR message there could be a number of issues,
we recommend having a deep diagnosis to pinpoint where the fault lies.
Common Faults leading to START ERROR on with certain Mercedes Benz:
Battery power not sufficient
The transponder in your key is faulty or missing
Antena coil on ignition faulty
Fuel pump fault
We also recommend testing for power on your WSP plug.
Pin 3 is continuous +12V direct from the battery, Red/Yellow Wire
Pin 7 is ignition +12V when your key is in position 1 and 2, Black /Yellow Wire
If there is no power on either you will get START ERROR on the dash.