Group 28
Troubleshooting
MID 128 PID 45 Preheater Status
The preheat relay is provided battery voltage at all times through the supply wire. If the
EECU requests preheat operation (based on engine temperature), the control wire will
be grounded through the EECU. Preheating is standard on the D7C engine with one
preheat relay/element. Preheating is optional on the D12B engine with two preheat re-
lays/elements.
Fault Codes
FMI 3
Short circuit to battery voltage.
Conditions for fault code:
•
Output activated.
•
Short circuit to battery voltage on EB31.
Possible cause:
•
Short circuit to battery voltage on wire between pre-
heating relay and EECU.
•
Short circuit in the preheating relay.
Reaction from the EECU:
•
Fault code is set.
•
Yellow lamp is requested.
•
The EECU switches off the output.
Noticeable external symptom:
•
Yellow lamp lights up.
•
The preheating relay is not activated.
•
White smoke for cold start.
•
Difficult to start in extreme cold.
FMI 4
Short circuit to ground.
Conditions for fault code:
•
Output switched off.
•
Short circuit to ground on EB31.
Possible cause:
•
Short circuit to ground on wire between preheating
relay and EECU.
Reaction from the EECU:
•
Fault code is set.
•
Yellow lamp is requested.
Noticeable external symptom:
•
Yellow lamp lights up.
•
The intake air is warm since the preheating relay is
on all the time.
•
High current consumption.
FMI 5:
Break
Conditions for fault code:
•
Output switched off.
•
Open circuit.
Possible cause:
•
Blown fuse to the supply for preheating relay.
•
Open circuit in wire between EECU and preheating
relay.
•
Open circuit in the preheating relay.
•
Open circuit in supply wire to preheating relay.
Reaction from the EECU:
•
Fault code is set.
•
Yellow lamp is requested.
•
The EECU switches off the output.
Noticeable external symptom:
•
Yellow lamp lights up.
•
The preheating relay is not activated.
•
White smoke for cold start.
•
Difficult to start in extreme cold.
95
Summary of Contents for TSI
Page 1: ......
Page 8: ...6...
Page 30: ...Group 28 Specifications Schematic D12B W2002827 28...
Page 31: ...Group 28 Specifications Schematic D12C W2003348 29...
Page 32: ...Group 28 Specifications Schematic D7C W2002826 30...
Page 33: ...Group 28 Specifications Schematic VECU W3003497 31...
Page 34: ...32...
Page 86: ...84...
Page 96: ...Group 28 Troubleshooting 94...
Page 110: ...Group 28 Troubleshooting Fuel Pressure Sensor Pres sure Voltage Chart W2002799 108...
Page 114: ...Group 28 Troubleshooting Oil Pressure Sensor Pres sure Voltage Chart W2002732 112...
Page 118: ...Group 28 Troubleshooting Boost Pressure Sensor Pres sure Voltage Chart W2002730 116...
Page 129: ...Group 28 Troubleshooting Coolant Temperature Sensor Tem perature Resistance Chart W2002729 127...
Page 140: ...Group 28 Troubleshooting Fuel Temperature Sensor Tempera ture Resistance Chart W2002742 138...
Page 144: ...Group 28 Troubleshooting Oil Temperature Sensor Tempera ture Resistance Chart W2002727 142...
Page 248: ......
Page 249: ...Operation Numbers 2841 03 02 01 Engine ECU Replacement 243...