199003090 - P0683 Preheating control unit (feedback)

This error is detected if there is a problem in the pre-heating circuit.
Test results
1GLOW PLUG OPERATION CHECKAll OKProblems encounteredOperation
Check that the heater plugs are working properly, by carrying out the    See Test 5520CA CHECK GLOW PLUG OPERATIONEnd of diagnosis--