6.1 Mechanical Troubleshooting

The first section of this chapter explains mechanical troubleshooting logic. The next section contains information for troubleshooting the electronic controls.

Information can be located by using the table of contents at the front of the manual.

Instructions to "Contact Detroit Diesel Customer Service Center" indicate that at the time of this publication, all known troubleshooting checks have been included. Review any recent Service Information Bulletins (SIB) or Service Information letters before calling.

If there is no physical evidence of mechanical failure, a failure of an electronic nature should be considered. This would include a faulty sensor or sensor hardware related concern. You are advised to consult the EPA07 Series 60 DDEC VI Troubleshooting Guide (DDC-SVC-MAN-0009), EPA07/10 DD Platform Troubleshooting Manual (DDC-SVC-MAN-0084), EPA07 MBE 900 DDEC VI Troubleshooting Guide (DDC-SVC-MAN-0015), EPA07 MBE 4000 DDEC VI Troubleshooting Guide (DDC-SVC-MAN-0010), or this ATS Guide for troubleshooting electronic faults.

To perform a parked regeneration, the required conditions listed in Table "Parked Regeneration Requirements" must be met.

Connect DDDL 7.X to monitor the inputs.

Symptom	Required Conditions
Unable to initiate Parked Regeneration via Regen Request Switch

Table , Parked Regeneration Requirements

Listed in Table "Mechanical Troubleshooting via Dash Switch" are the common symptoms and possible causes to guide you through mechanical troubleshooting if regeneration is not functioning properly when initiated via the dash switch.

Symptom	Possible Causes	Suggestions
A parked regeneration initiates and runs indefinitely. (Intake throttle on Series 60, DD15, and MBE 4000 or Exhaust Flap on MBE 900 closes, and there is no HEST Lamp after 25 minutes.)	Low fuel supply pressure	Manually test fuel pressure. Check for plugged fuel filters or aerated fuel.
	Fuel Doser Valve partially plugged	Monitor Doser Injection Status and Doser Fuel Line Pressure. A high Doser Injection Status during regen, usually greater than 25% and doser fuel line pressure close to engine fuel pressure indicate plugging.
	Intake Manifold Pressure Sensor inaccurate	Compare reading to BARO (key ON, engine OFF).
	DOC Outlet Temperature Sensor non-responsive	Compare temperatures before and after engine startup. No temperature change indicates sensor problem.
	Electronic Dosing Valve inoperative	Monitor fuel line pressure. Pressure should change when valve commanded to open (PWM > 0).
	Fuel Cutoff Valve inoperative	Monitor fuel compensation pressure. Pressure should change when valve commanded to 100%.
	DOC not active	Monitor temperature rise across DOC during regen. Little or no temperature rise indicates DOC not active.
A parked regeneration initiates and runs indefinitely. (Intake Throttle on Series 60, DD15, and MBE 4000 or Exhaust Flap on MBE 900 does NOT close, and there is no HEST Lamp after 25 minutes.)	Low coolant temperature	Monitor coolant temperature. Temperature should be greater than 60°C (140°F).
	High DOC Outlet temperature	Monitor DOC outlet temperature. Temperature should be greater than 100°C (212°F) prior to regen.
	Engine in smoke control mode	Monitor smoke control status during regen. Smoke control status should be 0.
A parked regeneration initiates but aborts. (Test ends after 10-15 minutes of activation of Intake Throttle on Series 60, DD15, and MBE 4000 or Exhaust Flap on MBE 900.)	DOC Inlet Temperature Sensor non-responsive	Monitor DOC inlet temperature. No temperature change after engine startup indicates sensor problem.
	Intake Throttle Valve not functioning properly	Listen for the ITV to sweep at key up.
	Turbo not functioning properly	Perform a turbo hysteresis test.
	Low output of Engine Fuel Injector	Check for plugged tip. Perform cylinder cut out test.
	Exhaust Flap not functioning properly (MBE 900)	Check solenoid supply voltage and air pressure.
	Aerated fuel	Check fuel for aeration.

Table , Mechanical Troubleshooting via Dash Switch

Listed in Table "Mechanical Troubleshooting via DDDL 7.X" are the common symptoms and possible causes to guide you through mechanical troubleshooting if regeneration is not functioning properly when initiated via DDDL 7.X.

Symptom	Possible Causes	Suggestions
A parked regeneration initiates and runs indefinitely. (Intake throttle on Series 60, DD15, and MBE 4000 or Exhaust Flap on MBE 900 closes, and there is no HEST Lamp after 25 minutes.)	Low fuel supply pressure	Manually test fuel pressure. Check for plugged fuel filters or aerated fuel.
	Fuel Doser Valve partially plugged	Monitor Doser Injection Status and Doser Fuel Line Pressure. A high Doser Injection Status during regen, usually greater than 25% and Doser Fuel Line Pressure close to engine fuel pressure indicate plugging.
	Intake Manifold Pressure Sensor inaccurate	Compare reading to BARO (key ON, engine OFF).
	DOC Outlet Temperature Sensor non-responsive	Compare temperatures before and after engine startup. No temperature change indicates sensor problem.
	Electronic Dosing Valve inoperative	Monitor fuel line pressure. Pressure should change when valve commanded to open (PWM > 0).
	Fuel Cutoff Valve inoperative	Monitor fuel compensation pressure. Pressure should change when valve commanded to 100%.
	DOC not active	Monitor temperature rise across DOC during regen. Little or no temperature rise indicates DOC not active.
	DOC Inlet Temperature Sensor non-responsive	Monitor DOC inlet temperature. No temperature change after engine startup indicates sensor problem.
	Intake Throttle Valve not functioning properly	Listen for the ITV to sweep at key up.
	Turbo not functioning properly	Perform a turbo hysteresis test.
	Low output of Engine Fuel Injector	Check for plugged tip. Perform cylinder cut out test.
	Exhaust Flap not functioning properly (MBE 900)	Check solenoid supply voltage and air pressure.
	Aerated fuel	Check fuel for aeration.
A parked regeneration initiates and runs indefinitely. (Intake Throttle on Series 60, DD15, and MBE 4000 or Exhaust Flap on MBE 900 does NOT close, and there is no HEST Lamp after 25 minutes.)	Low coolant temperature	Monitor coolant temperature. Temperature should be greater than 60°C (140°F).
	High DOC Outlet temperature	Monitor DOC outlet temperature. Temperature should be greater than 100°C (212°F) prior to regen.
	Engine in smoke control mode	Monitor smoke control status during regen. Smoke control status should be 0.

Table , Mechanical Troubleshooting via DDDL 7.X