MBE 4000 SERVICE MANUAL 6SE412
Problem—The Engine Is in Emergency Running Mode (constant speed 1,300 rpm)
Cause
Remedy
The PLD or VCU control unit is damaged.
Bring the vehicle to an authorized dealer for service.
Problem—The Coolant Temperature Is Above Normal
Cause
Remedy
The coolant level is too low.
Check for coolant leaks, and repair as needed.
The poly-V belt is loose.
Tighten or replace the poly-V belt.
The coolant temperature gauge and/or sensor is not
reading correctly.
Bring the vehicle to an authorized dealer for service.
The radiator is damaged or dirty.
Clean the radiator. Repair or replace the radiator if
necessary.
The coolant pump is damaged.
Have an authorized dealer replace the coolant pump.
The thermostat is damaged.
Have an authorized dealer replace the coolant pump.
The fan is not operating properly.
Bring the vehicle to an authorized dealer and have the
fan hub checked.
Bring the vehicle to an authorized dealer and have the
parameter settings reprogrammed in the engine control
unit (PLD) or vehicle control unit (VCU).
Problem—The Coolant Temperature Is Below Normal
Cause
Remedy
The coolant temperature gauge and/or sensor is not
reading correctly.
Bring the vehicle to an authorized dealer for service.
The thermostat is damaged.
Have an authorized dealer replace the thermostat.
The fan is not operating properly.
Bring the vehicle to an authorized dealer and have the
fan hub checked.
Bring the vehicle to an authorized dealer and have the
parameter settings reprogrammed in the engine control
unit (PLD) or vehicle control unit (VCU).
Problem—The Cooling System Is Losing Coolant
Cause
Remedy
There is an external coolant leak.
Repair the leaking component.
The radiator cap is leaking.
Replace the radiator cap.
The air compressor head is damaged.
Have an authorized dealer replace the air compressor.
The cylinder head gasket is leaking.
Have an authorized dealer replace the head gasket.
All information subject to change without notice.
(Rev. 2007)
6SE412 0702
Copyright © 2007 DETROIT DIESEL CORPORATION
From Bulletin 1–MBE 4000–07
16-7