MIL Operation
The MIL is located on the instrument panel cluster (IPC).
MIL Function
- The MIL informs the driver that a malfunction has occurred and the vehicle should be taken in for service as soon as possible.
- The MIL illuminates during a bulb test and a system test.
- A DTC will be stored if a MIL is requested by the ECM.
MIL Illumination
- The MIL will illuminate with the ignition switch ON and the engine not running.
- The MIL will turn OFF when the engine is started.
- The MIL will remain ON if the self-diagnostic system has detected a malfunction.
- The MIL may turn OFF if the malfunction is not present.
- If the MIL is illuminated and then the engine stalls, the MIL will remain illuminated as long as the ignition switch is ON.
- If the MIL is not illuminated and the engine stalls, the MIL will not illuminate until the ignition switch is cycled OFF, then ON.
Test Description
The number below refers to the step number on the diagnostic table.
- 4: This step tests for a short to voltage on the MIL control circuit. With the fuse removed there should be no voltage on the MIL control circuit.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views | ||||
| 1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | Go to Diagnostic System Check - Engine Controls | |
| 2 | Verify whether the instrument cluster is operational. If the instrument panel (IP) is completely inoperative, refer to Diagnostic System Check - Instrument Cluster in Instrument Panel, Gages and Console. Command the MIL ON and OFF with a scan tool. Does the MIL turn ON and OFF when commanded with a scan tool? | Go to Intermittent Conditions | Go to Step 3 | |
| 3 | Inspect the fuse that supplies battery voltage to the cluster. Is the fuse open? | Go to Step 10 | Go to Step 4 | |
| 4 | Turn OFF the ignition. Remove the fuse that supplies battery voltage to the cluster. Disconnect the Engine Control Module (ECM). Turn ON the ignition with the engine OFF. Measure the voltage from the MIL control circuit in the ECM harness connector to a good ground. Is the voltage less than the specified value? | 1.0 V | Go to Step 5 | Go to Step 11 |
| 5 | Turn OFF the ignition. Install the fuse that supplies battery voltage to the cluster. Turn ON the ignition with the engine OFF. Connect a 3-amp fused jumper wire between the MIL control circuit in the ECM harness connector and a good ground. Is the MIL illuminated? | Go to Step 9 | Go to Step 6 | |
| 6 | Turn OFF the ignition. Remove the instrument panel cluster (IPC). Refer to Instrument Panel Cluster (IPC) Replacement in Instrument Panel, Gages, and Console. Turn ON the ignition, with the engine OFF. Probe the battery voltage circuit of the IPC harness connector with a test lamp that is connected to a good ground. Does the test lamp illuminate? | Go to Step 7 | Go to Step 12 | |
| 7 | Test the MIL control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct a condition? | Go to Step 15 | Go to Step 8 | |
| 8 | Test for an intermittent and for a poor connection at the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 15 | Go to Step 13 | |
| 9 | Test for an intermittent and for a poor connection at the ECM. Refer to Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 15 | Go to Step 14 | |
| 10 | Test all circuits and components that are supplied by this fuse for excessive current draw. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 15 | Go to Intermittent Conditions | |
| 11 | Repair the short to voltage in the MIL control circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 15 | ||
| 12 | Repair the open in the battery voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 15 | ||
| 13 | Replace the IPC. Refer to Instrument Panel Cluster (IPC) Replacement in Instrument Panel, Gauges, and Console. Did you complete the replacement? | Go to Step 15 | ||
| 14 | Replace the ECM. Refer to Engine Control Module (ECM) Replacement . Did you complete the replacement? | Go to Step 15 | ||
| 15 | Turn OFF the ignition for 30 seconds. Start the engine. Does the MIL operate correctly? | Go to Step 16 | Go to Step 2 | |
| 16 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | Go to Diagnostic Trouble Code (DTC) List | System OK | |
Malfunction Indicator Lamp (MIL) Inoperative
The MIL is located on the instrument panel (IPC).
MIL Function
- The MIL informs the driver that a malfunction has occurred and the vehicle should be taken in for service as soon as possible.
- The MIL illuminates during a bulb test and a system test.
- A DTC will be stored if a MIL is requested by the ECM.
MIL Illumination
- The MIL will illuminate with ignition switch ON and the engine not running.
- The MIL will turn OFF when the engine is started.
- The MIL will remain ON if the self-diagnostic system has detected a malfunction.
- The MIL may turn OFF if the malfunction is not present.
- If the MIL is illuminated and then the engine stalls, the MIL will remain illuminated so long as the ignition switch is ON.
- If the MIL is not illuminated and the engine stalls, the MIL will not illuminate until the ignition switch is cycled OFF, then ON.
The number below refers to the step number on the diagnostic table.
- 2: This step determines if the condition is with the MIL control circuit or the PCM.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views | |||
| 1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | Go to Diagnostic System Check - Engine Controls |
| 2 | Turn OFF the ignition. Disconnect the ECM. Turn ON the ignition, with the engine OFF. Observe the MIL. Is the MIL illuminated? | Go to Step 3 | Go to Step 5 |
| 3 | Remove the instrument panel cluster (IPC). Refer to Instrument Panel Cluster (IPC) Replacement in Instrument Panel, Gages, and Console. Test the MIL control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 6 | Go to Step 4 |
| 4 | Replace the IPC. Refer to Instrument Panel Cluster (IPC) Replacement in Instrument Panel, Gages, and Console. Did you complete the replacement? | Go to Step 6 | |
| 5 | Replace the ECM. Refer to Engine Control Module (ECM) Replacement . Did you complete the replacement? | Go to Step 6 | |
| 6 | Turn the ignition OFF for 30 seconds. Start the engine. Does the vehicle operate correctly without any MIL illumination, and without any stored DTCs? | System OK | Go to Diagnostic System Check - Engine Controls |
Malfunction Indicator Lamp (MIL) Always On
The numbers below refer to the step numbers on the diagnostic table.
- 5: This step tests for an ignition 1 voltage supply to the engine control module (ECM).
- 6: This step tests the 12-volt reference circuit to the CKP sensor and the CMP sensor. The 12-volt reference circuit for the CKP sensor and the CMP sensor is connected internally within the ECM. If the 12-volt reference circuit is shorted to ground, the engine will not start and no engine speed will be indicated on the scan tool.
- 8: If there is fuel in the engine oil, fuel may be leaking from the fuel injector or fuel injection pump into the crankcase.
- 9: If the fuel system will not even briefly prime to 10 psi and will not start, the check valve in the fuel filter/heater element housing is stuck open.
- 10: This step determines if the fuel system is bleeding down causing a no start. The fuel pressure will slowly drop to 0 psi, but should still be above 8 psi 10 seconds after pressurizing the fuel system.
- 12: This step determines if the problem is a stuck open or broken fuel injector. If fuel vapors come out of any of the glow plug holes, excessive fuel is being sent into a cylinder, and not being distributed to all of the fuel injectors.
- 13: The engine will not run without an actual fuel rail pressure more than 10 MPa (1,450 psi).
- 15: If the no-start condition takes place in cold operating temperatures, 2-4° C (35-40° F) or colder, a glow plug system failure may cause the no-start condition.
- 17: In some cases, no compression, possibly with excessive fuel, in a single cylinder can cause a no start.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 | Did you perform the Diagnostic System Check - Engine Controls? | Go to Step 2 | Go to Diagnostic System Check - Engine Controls | |
| 2 | Turn On the ignition, with the engine OFF. Observe the DTC Information with a scan tool. Does the scan tool display DTC P0090, P0335, P0336, P0340, P0370, P0374, P0380, P0601, P0602, P0603, P0604, P0611, P0612, P1621, P1626, P1631, P1683, or U1800? | Go to Diagnostic Trouble Code (DTC) List | Go to Step 3 | |
| 3 | Is the customer's concern with a fuel smell or fuel leak? | Go to Fuel Leaks (Outside of Engine) or Fuel Leaks (Inside of Engine) | Go to Step 4 | |
| 4 | Observe the Actual Fuel Rail Pressure parameter with a scan tool. Is the pressure within the specified range? | 1-1.8 MPa | Go to Step 5 | Go to Step 18 |
| 5 | Observe the Ignition 1 signal parameter with a scan tool. Is the Ignition 1 signal parameter at the specified value? | B+ | Go to Step 6 | Go to Step 24 |
| 6 | Attempt to start the engine. Observe the Engine Speed parameter with a scan tool while the engine is cranking. Is the Engine Speed parameter more than the specified value? | 0 RPM | Go to Step 7 | Go to Step 19 |
| 7 | IMPORTANT: If there is high resistance in the signal or low reference circuits of the crankshaft position (CKP) sensor the Engine Speed parameter of the scan tool will display a value more than 0. It will not be an accurate measure of engine speed, and can cause an Engine Cranks but does Not Run condition. Test the CKP sensor signal and low reference circuits for high resistance. Refer to Circuit Testing in Wiring Systems.Did you find and correct the condition? | Go to Step 34 | Go to Step 8 | |
| 8 | Inspect for the following conditions: Excessive fuel in the engine oil-Refer to Fuel in Engine Oil in Engine Mechanical. Contaminated Fuel-Refer to Contaminants-in-Fuel Diagnosis . Did you find and correct the condition? | Go to Step 34 | Go to Step 9 | |
| 9 | Install the J 44638 Vacuum Gage to the fuel system service port on the right front side of the engine. Attempt to hand prime the fuel manager 30 times or until the specified pressure is reached. Can you prime the system to the specified value? | 8 psi | Go to Step 10 | Go to Step 31 |
| 10 | Does the pressure measure more than the specified value for more than 2 minutes? | 2 psi | Go to Step 11 | Go to Step 14 |
| 11 | Perform the Engine Compression Test. Refer to Engine Compression Test in Engine Mechanical - 6.6L. Repair the engine as necessary. Did you find and correct the condition? | Go to Step 34 | Go to Step 12 | |
| 12 | Did any of the cylinders emit any fuel vapor during the Engine Compression Test? | Go to Step 28 | Go to Step 13 | |
| 13 | Crank the engine for 15 seconds. Observe the Actual Fuel Rail Pressure parameter with a scan tool. Is the Actual Fuel Rail Pressure parameter more than the specified value? | 10 MPa (1,450 psi) | Go to Step 15 | Go to Step 14 |
| 14 | Reprime the fuel manager to 10 psi. Attempt to start the engine while the prime is still above 8 psi. Does the engine start? | Go to Fuel System Diagnosis (Pickup) or Fuel System Diagnosis (Cab Chassis) | Go to Fuel System Diagnosis - High Pressure Side | |
| 15 | Observe the Glow Plug System Type parameter with a scan tool. Is the Glow Plug System Type Federal? | Go to Step 16 | Go to Step 17 | |
| 16 | IMPORTANT: Repeat this procedure on both banks of the engine. This test may be repeated as many times as necessary. Turn OFF the ignition. Connect a test lamp to a glow plug harness connector on one side of the engine. Turn ON the ignition, with the engine OFF. Does the test lamp turn ON and OFF? | Go to Step 17 | Go to Glow Plug System Diagnosis | |
| 17 | Inspect for the following conditions: A plugged air filter A collapsed air intake duct The fuel heater is inoperative. If the customer concern is that the engine will not start when ambient temperatures are less than 2-4° C (35-40° F), refer to Fuel Heater Inoperative . A restricted exhaust system-Refer to Symptoms - Engine Exhaust in Engine Exhaust. Did you find and correct the condition? | Go to Step 34 | Go to Diagnostic Aids | |
| 18 | Disconnect the fuel rail pressure (FRP) sensor. Observe the Actual Fuel Rail Pressure parameter on the scan tool. Does the Actual Fuel Rail Pressure parameter measure more than the specified value? | 175 MPa | Go to Step 23 | Go to Step 22 |
| 19 | Turn OFF the ignition. Disconnect the CKP sensor. Turn ON the ignition, with the engine OFF. Probe the 12-volt reference circuit of the CKP sensor with a DMM connected to a good ground. Is the voltage more than the specified value? | 10 V | Go to Step 29 | Go to Step 20 |
| 20 | Turn OFF the ignition. Disconnect the camshaft position (CMP) sensor. Turn ON the ignition, with the engine OFF. Probe the 12-volt reference circuit of the CMP sensor with a DMM connected to a good ground. Is the voltage more than the specified value? | 10 V | Go to Step 30 | Go to Step 21 |
| 21 | Test the 12-volt reference circuit of the CKP sensor and the CMP sensor for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 34 | Go to Step 33 | |
| 22 | Test the FRP sensor signal circuit for a short to ground. Refer to Circuit Testing in Wiring Systems. Did you find and correct the condition? | Go to Step 34 | Go to Step 33 | |
| 23 | Test the FRP sensor circuits for high resistance. Refer to Circuit Testing in Wiring Systems. Did you find and correct the condition? | Go to Step 34 | Go to Step 25 | |
| 24 | Test the ignition 1 voltage circuit of the engine control module (ECM) for a short to ground, a high resistance, or an open. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Replace the fuse if necessary. Did you find and correct the condition? | Go to Step 34 | Go to Step 26 | |
| 25 | Test for an intermittent or for a poor connection at the FRP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 34 | Go to Step 32 | |
| 26 | Clean and tighten the ECM shared ground. Refer to Power and Grounding Component Views in Wiring Systems. Attempt to start the engine. Does the engine start? | Go to Step 34 | Go to Step 27 | |
| 27 | Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 34 | Go to Step 33 | |
| 28 | IMPORTANT: When the fuel injector pressure lines are removed, debris will fall on the fuel injector inlet fitting. Vacuum the debris from the area to prevent the debris from falling in the fuel injector. Replace the fuel injectors on the affected cylinders. Refer to Fuel Injector Replacement .Did you complete the replacement? | Go to Step 34 | ||
| 29 | Replace the CKP sensor. Refer to Crankshaft Position (CKP) Sensor Replacement . Did you complete the replacement? | Go to Step 34 | ||
| 30 | Replace the CMP sensor. Refer to Camshaft Position (CMP) Sensor Replacement . Did you complete the replacement? | Go to Step 34 | ||
| 31 | IMPORTANT: Before replacing the fuel filter/heater element housing, inspect the fuel vent screw for damage or cross threading. Replace the vent screw w/"O" ring if either condition is found. Replace the fuel filter/heater element housing. Refer to Fuel Filter/Heater Element Housing Replacement .Did you complete the replacement? | Go to Step 34 | ||
| 32 | Replace the FRP sensor. Refer to Fuel Rail Pressure (FRP) Sensor Replacement . Did you complete the replacement? | Go to Step 34 | ||
| 33 | Replace the engine control module (ECM). Refer to Engine Control Module (ECM) Replacement . Did you complete the replacement? | Go to Step 34 | ||
| 34 | Clear any DTCs with a scan tool. Attempt to start the engine. Does the engine start and continue to run? | Go to Step 35 | Go to Step 2 | |
| 35 | Allow the engine to idle until normal operating temperature is reached. Observe the DTC Information with a scan tool. Are any DTCs displayed? | Go to Diagnostic Trouble Code (DTC) List | System OK |
| IMPORTANT |
|---|
| If there is high resistance in the signal or low reference circuits of the crankshaft position (CKP) sensor the Engine Speed parameter of the scan tool will display a value more than 0. It will not be an accurate measure of engine speed, and can cause an Engine Cranks but does Not Run condition. |
| IMPORTANT |
|---|
| Repeat this procedure on both banks of the engine. This test may be repeated as many times as necessary. |
| IMPORTANT |
|---|
| When the fuel injector pressure lines are removed, debris will fall on the fuel injector inlet fitting. Vacuum the debris from the area to prevent the debris from falling in the fuel injector. |
| IMPORTANT |
|---|
| Before replacing the fuel filter/heater element housing, inspect the fuel vent screw for damage or cross threading. Replace the vent screw w/"O" ring if either condition is found. |
Engine Cranks but Does Not Run
Fuel System Description
If the fuel supply system is not delivering enough fuel driveability could be greatly affected. If air is being drawn into the fuel injection system a Cranks But Will Not Run, or a Hard Start symptom could exist. If another diagnosis indicates, or if the fuel supply system is suspected of not delivering enough fuel or drawing air, the following systems should be checked
- Any air leaks or restrictions between the fuel injection pump and the fuel tank will seriously affect pump output.
- Insufficient fuel in the fuel tank
- Any loose fuel component connections
- Any hoses and lines that are flattening when the engine is running, or have kinks that would restrict the flow of fuel
If the fuel supply system is not delivering enough fuel driveability could be greatly affected. If air is being drawn into the fuel injection system a Cranks But Will Not Run, or a Hard Start symptom could exist. If another diagnosis indicates, or if the fuel supply system is suspected of not delivering enough fuel or drawing air, the following systems should be checked
- Any air leaks or restrictions between the fuel injection pump and the fuel tank will seriously affect pump output.
- Insufficient fuel in the fuel tank.
- Any loose fuel component connections.
- Any hoses and lines that are flattening when the engine is running, or have kinks that would restrict the flow of fuel.
The numbers below refer to the step numbers on the diagnostic table.
- 4: The balance rate adjustments are utilized by the ECM only at idle. The balance rates are the fuel adjustments for each individual cylinder based on the variations in engine crankshaft speed. A positive value indicates that fuel is being added to each cylinder event, such as with poor engine compression or a fuel injector that is not flowing enough fuel. A negative value indicates fuel being removed from each cylinder event, such as a fuel injector that is flowing too much fuel. The balance rates will change depending on if the transmission is in Neutral or Drive.
- 5: This step determines if the ECM can control a stable fuel pressure. A high balance rate may be caused by a fuel injector or compression only if the ECM can control fuel pressure.
- 6: The Cylinder Power Balance Test may be performed at any engine speed or load from idle to wide-open throttle. There is a 5 minute time limit for each test. The ECM and scan tool must both be powered down to reset the timer.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 | Did you perform the Diagnostic System Check - Engine Controls? | Go to Step 2 | Go to Diagnostic System Check - Engine Controls | |
| 2 | Are any DTCs set other than P0300, P0301-P0308? | Go to Diagnostic Trouble Code (DTC) List | Go to Step 3 | |
| 3 | Does the customer concern occur ONLY at idle or during tip-in acceleration off-idle? | Go to Step 4 | Go to Step 6 | |
| 4 | Start and run the engine until the engine coolant temperature is more than 82° C (180° F). Turn OFF all accessories. Hold the brake pedal in the fully applied position. A hiss will be noticeable when the brake is fully applied. Place the transmission in Drive. Idle the engine for more than 30 seconds. Record the Balancing Rate Cyl.1-8 parameters from the scan tool while the engine is at idle speed. Repeat steps 2-6 with the transmission in Neutral. Are all of the Balancing Rate parameters within the first specified range in Drive, and the second specified range in Neutral? | 6 mm 3 and +6 mm 3 -4 mm 3 and +4 mm 3 | Go to Step 6 | Go to Step 5 |
| 5 | Graph the Fuel Pressure Regulator. Refer to Fuel System Diagnosis - High Pressure Side . Is the fuel pressure regulator graph normal? | Go to Step 7 | Go to Step 9 | |
| 6 | IMPORTANT: The fuel Cylinder Power Balance Test must be performed under the conditions for which the concern occurred. The concern must be duplicated during the test. IMPORTANT: Do not operate the cruise control during this test. Cruise control reactivation after the test may cause a brief extreme increase in engine speed. Observe the cylinder power contribution or other customer concern. Perform the Cylinder Power Balance Test in Special Functions. Do any of the cylinders indicate a different cylinder power contribution than the others, or lessen the customer concern? | Go to Step 7 | System OK | |
| 7 | IMPORTANT: A fuel injector leak into the combustion chamber may result in mechanical damage to the cylinder. If any fuel spray comes out of a glow plug hole during the compression test, replace the fuel injector of the affected cylinder. Perform the Engine Compression Test. Refer to Engine Compression Test in Engine Mechanical - 6.6LDo any of the cylinders have low compression? | Go to Symptoms - Engine Mechanical in Engine Mechanical - 6.6L | Go to Step 8 | |
| 8 | IMPORTANT: Refer to Injection System Components in Engine Controls Component Views . Failure to correctly identify the cylinder positions may result in the replacement of the wrong fuel injector. Replace the fuel injectors on the cylinders that had poor cylinder power contribution, high balance rates, or a noise/smoke change. Refer to Fuel Injector Replacement .Did you complete the replacements? | Go to Step 10 | ||
| 9 | Replace the fuel pressure regulator. Refer to Fuel Pressure Regulator Replacement . Did you complete the replacement? | Go to Step 10 | ||
| 10 | Operate the vehicle under the conditions in which the concern occurred. Does the system operate normally, with no DTCs or symptoms? | System OK | Go to Symptoms - Engine Controls |
| IMPORTANT |
|---|
| The fuel Cylinder Power Balance Test must be performed under the conditions for which the concern occurred. The concern must be duplicated during the test. |
| IMPORTANT |
|---|
| Do not operate the cruise control during this test. Cruise control reactivation after the test may cause a brief extreme increase in engine speed. |
| IMPORTANT |
|---|
| A fuel injector leak into the combustion chamber may result in mechanical damage to the cylinder. If any fuel spray comes out of a glow plug hole during the compression test, replace the fuel injector of the affected cylinder. |
| IMPORTANT |
|---|
| Refer to Injection System Components in Engine Controls Component Views . Failure to correctly identify the cylinder positions may result in the replacement of the wrong fuel injector. |
Fuel Injector Balance Test with Tech 2 (with Automatic Transmission)
The numbers below refer to the step numbers on the diagnostic table.
- 2: If the majority of the balance rates are positive and high, the dual-mass flywheel is causing a harmonic vibration that is affecting the engine fuel control system.
- 3: A dual mass flywheel concern will cause the balance rates to be inaccurate. The transmission concerns must be repaired before any fuel system diagnostic can be performed.
- 4: The balance rates are only to be used to diagnose these specific concerns.
- 5: The balance rate adjustments are utilized by the ECM only at idle. The balance rates are the fuel adjustments for each individual cylinder based on the variations in engine crankshaft speed. A positive value indicates that fuel is being added to each cylinder event, such as with poor engine compression or a fuel injector that is not flowing enough fuel. A negative value indicates fuel being removed from each cylinder event, such as a fuel injector that is flowing too much fuel.
- 6: This step determines if the ECM can control a stable fuel pressure. A high balance rate may be caused by a fuel injector or compression only if the ECM can control fuel pressure.
- 7: The Cylinder Power Balance Test may be performed at any engine speed or load from idle to wide-open throttle. There is a 5 minute time limit for each test. The ECM and scan tool must both be powered down to reset the timer.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | Go to Diagnostic System Check - Engine Controls | |
| 2 | Start and run the engine until the engine coolant temperature is more than 82° C (180° F). Turn OFF all accessories. Hold the brake pedal in the fully applied position. A hiss will be noticeable when the brake is fully applied. Idle the engine for more than 30 seconds. Record the Balancing Rate Cyl.1-8 parameters from the scan tool while the engine is at idle speed. Are at least 5 of the Balancing Rate parameters more than the specified value? | +4 mm 3 | Go to Engine Flywheel Replacement - Manual Transmission in Engine Mechanical | Go to Step 3 |
| 3 | Are any DTCs set other than P0300, P0301-P0308? | Go to Diagnostic Trouble Code (DTC) List | Go to Step 4 | |
| 4 | Does the customer concern occur ONLY at idle or during tip-in acceleration off-idle? | Go to Step 5 | Go to Step 7 | |
| 5 | Start and run the engine until the engine coolant temperature is more than 82° C (180° F). Turn OFF all accessories. Hold the brake pedal in the fully applied position. A hiss will be noticeable when the brake is fully applied. Idle the engine for more than 30 seconds. Record the Balancing Rate Cyl.1-8 parameters from the scan tool while the engine is at idle speed. Are all of the Balancing Rate parameters within the specified range? | 4 mm 3 and +4 mm 3 | Go to Step 7 | Go to Step 6 |
| 6 | Graph the Fuel Pressure Regulator. Refer to Fuel System Diagnosis - High Pressure Side . Is the fuel pressure regulator graph normal? | Go to Step 8 | Go to Step 10 | |
| 7 | IMPORTANT: The fuel Cylinder Power Balance Test must be performed under the conditions for which the concern occurred. The concern must be duplicated during the test. IMPORTANT: Do not operate the cruise control during this test. Cruise control reactivation after the test may cause a brief extreme increase in engine speed. Observe the cylinder power contribution or other customer concern. Perform the Cylinder Power Balance Test in Special Functions. Do any of the cylinders indicate a different cylinder power contribution than the others, or lessen the customer concern? | Go to Step 8 | System OK | |
| 8 | IMPORTANT: A fuel injector leak into the combustion chamber may result in mechanical damage to the cylinder. If any fuel spray comes out of a glow plug hole during the compression test, replace the fuel injector of the affected cylinder. Perform the Engine Compression Test. Refer to Engine Compression Test in Engine Mechanical-6.6LDo any of the cylinders have low compression? | Go to Symptoms - Engine Mechanical in Engine Mechanical-6.6L | Go to Step 9 | |
| 9 | IMPORTANT: Refer to Injection System Components in Engine Controls Component Views . Failure to correctly identify the cylinder positions may result in the replacement of the wrong fuel injector. Replace the fuel injectors on the cylinders that had poor cylinder power contribution, high balance rates, or a noise/smoke change. Refer to Fuel Injector Replacement .Did you complete the replacements? | Go to Step 11 | ||
| 10 | Replace the fuel pressure regulator. Refer to Fuel Pressure Regulator Replacement . Did you complete the replacement? | Go to Step 11 | ||
| 11 | Operate the vehicle under the conditions in which the concern occurred. Does the system operate normally, with no DTCs or symptoms? | System OK | Go to Symptoms - Engine Controls |
| IMPORTANT |
|---|
| The fuel Cylinder Power Balance Test must be performed under the conditions for which the concern occurred. The concern must be duplicated during the test. |
| IMPORTANT |
|---|
| Do not operate the cruise control during this test. Cruise control reactivation after the test may cause a brief extreme increase in engine speed. |
| IMPORTANT |
|---|
| A fuel injector leak into the combustion chamber may result in mechanical damage to the cylinder. If any fuel spray comes out of a glow plug hole during the compression test, replace the fuel injector of the affected cylinder. |
| IMPORTANT |
|---|
| Refer to Injection System Components in Engine Controls Component Views . Failure to correctly identify the cylinder positions may result in the replacement of the wrong fuel injector. |
Fuel Injector Balance Test with Tech 2 (with Manual Transmission)
Description
Several states require that a vehicle pass on-board diagnostic (OBD) system tests and the I/M emission inspection in order to renew license plates. This is accomplished by viewing the I/M System Status display on a scan tool. Using a scan tool, the technician can observe the I/M System Status in order to verify that the vehicle meets the criteria that complies with the local area requirements.
The numbers below refer to the step numbers on the diagnostic table.
- 1: Any DTCs set, even those that are not listed in the Inspection/Maintenance System DTC table, may prevent the required DTCs from running. If there is any question as to whether a set DTC is disabling the required I/M diagnostic, review the Conditions for Running in the diagnostic procedures for the DTC required by the I/M diagnostic. A list of disabling DTCs, if applicable, is contained in the supporting text for that DTC.
- 2: Anytime a control module is reprogrammed or the diagnostic trouble codes are cleared as part of a repair procedure, all the I/M System Status indicators will reset to NO.
- 3: Use discretion when determining whether the entire I/M Complete System Set Procedure needs to be performed. For example, if the only tests that have not run are those that require the engine to be at operating temperature, then only those individual tests need to be run. There is no need to allow the engine to completely cool in order to run these tests.
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Perform the Diagnostic System Check - Engine Controls . IMPORTANT: Many DTC related repairs will instruct the technician to clear the DTC information. This procedure will reset ALL of the I/M System Status indicators to NO, and require performing the I/M Complete System Set Procedure (Diesel). Repair any DTCs or driveability concerns that would prevent the I/M System Status tests from completing. Did you find and repair a DTC or driveability concern? | Go to Step 3 | Go to Step 2 |
| 2 | Review any service bulletins for software updates that may prevent I/M readiness. Perform any reprogramming or repairs indicated by the service bulletins. Was a reprogramming or repair service required? | Go to Inspection/Maintenance (I/M) Complete System Set Procedure | Go to Step 3 |
| 3 | With a scan tool, observe the I/M System Status display. Is more than one test indicating a NO status? | Go to Inspection/Maintenance (I/M) Complete System Set Procedure | Go to the I/M System Set Procedure for the indicated system |
| IMPORTANT |
|---|
| Many DTC related repairs will instruct the technician to clear the DTC information. This procedure will reset ALL of the I/M System Status indicators to NO, and require performing the I/M Complete System Set Procedure (Diesel). |
Inspection/Maintenance (I/M) System Check
The purpose of the I/M Complete System Set Procedure is to satisfy the enable criteria necessary to execute all of the I/M readiness diagnostic tests, and complete the trips for those particular diagnostic tests. When all diagnostic tests are completed, the I/M System Status indicators are set to YES. Perform this test when more than one of the I/M System Status indicators are set to NO.
The numbers below refer to the step numbers on the diagnostic table.
- 1: Ensure that you perform the I/M System Check before performing this test. Failure to do so may result in difficulty updating the status to YES.
- 2: This step initiates the Component Monitoring Tests.
- 3: The cruise portion of the step runs a portion of the Component Monitoring Tests and to prepare for the remaining tests.
- 4: The acceleration portion of the step completes the Component Monitoring Tests and the idle portion completes the Misfire Monitoring diagnostic tests.
- 5: Perform the individual system test for any of the systems that do not update to YES.
- 6: The I/M System Status only reports on whether or not a diagnostic test has run, not the outcome of the test. If any emission related DTC sets after the tests are complete, the DTC will require diagnosis.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 | Did you perform the Inspection/Maintenance (I/M) System Check? | Go to Step 2 | Go to Inspection/Maintenance (I/M) System Check | |
| 2 | IMPORTANT: Once the engine is started, DO NOT turn the engine OFF for the remaining portion of the set procedure. Ensure the vehicle is within the Conditions for Running specified in the supporting text. Turn OFF all of the accessories, e.g., A/C, blower fan, etc. Set the vehicle parking brake. Verify the transmission is in Park for automatic transmissions and Neutral for manual transmissions. Start the engine, and allow the engine to idle. IMPORTANT: Do not let the engine idle for more than the specified time. Extended idling may prevent some of the required tests from running. Allow the engine to idle for the specified time. Did you complete the action? | 2 minutes | Go to Step 3 | |
| 3 | CAUTION: Refer to Road Test Caution in Cautions and Notices. In order for the next group of tests to run, the vehicle must operate in the following conditions: Acceleration at part throttle to 80 km/h (50 mph) with this speed maintained until the engine reaches operating temperature. This may be up to 10 minutes depending on the start up coolant temperature. Continued operation under these conditions for an additional 3 minutes. Did you complete the action? | Go to Step 4 | ||
| 4 | CAUTION: Refer to Road Test Caution in Cautions and Notices. In order for the next group of tests to run, the vehicle must operate in the following conditions: Acceleration at 75 percent throttle until a speed of 110 km/h (68 mph) is attained. Deceleration to 0 km/h (0 mph). Engine idling for 2 minutes while the following criteria is maintained: Service brake depressed Automatic transmission in Drive Manual transmission in Neutral with the clutch pedal depressed Did you complete the action? | Go to Step 5 | ||
| 5 | Observe the I/M System Status with a scan tool. Did all of the I/M System Status indicators update to YES? | Go to Step 6 | Go to the I/M System Set Procedure for the indicated systems | |
| 6 | Observe the Emission Related DTC portion of the I/M System Status with a scan tool. Does the scan tool indicate any Emission Related DTCs set? | Go to Diagnostic Trouble Code (DTC) List | System OK |
| IMPORTANT |
|---|
| Once the engine is started, DO NOT turn the engine OFF for the remaining portion of the set procedure. |
| IMPORTANT |
|---|
| Do not let the engine idle for more than the specified time. Extended idling may prevent some of the required tests from running. |
| CAUTION |
|---|
| Refer to Road Test Caution in Cautions and Notices. |
| CAUTION |
|---|
| Refer to Road Test Caution in Cautions and Notices. |
Inspection/Maintenance (I/M) Complete System Set Procedure
The purpose of this procedure is to satisfy the enable criteria necessary to execute an inspection/maintenance (I/M) system monitor for the exhaust gas recirculation (EGR). The system monitor is comprised of the test results from one or more DTCs. This procedure may be used to set the EGR I/M System Status display on the scan tool to YES. The EGR I/M System Status display indicated whether or not the control module has completed the system monitor. The system monitor completes when either all DTCs comprising the monitor run and pass, or any DTC comprising the monitor illuminates the malfunction indicator lamp (MIL). If one of the DTCs comprising the monitor is set and the MIL is not illuminated, the necessary trips are required to illuminate the MIL before the monitor will complete. Once the monitor completes, the EGR I/M System Status display will be updated to YES.
The purpose of this test is to satisfy the enable criteria necessary to execute I/M readiness diagnostic tests for the Misfire Monitoring System. The test may be used to set the I/M System Status to YES. Make sure that the vehicle meets the requirements in Conditions for Running before performing this test. Failure to meet the necessary requirements may produce inaccurate test results.
The numbers below refer to the step numbers on the diagnostic table.
- 1: Ensure that you perform the I/M System Check before performing this test. Failure to do so may result in difficulty updating the status to YES.
- 3: This step identifies a first failure of a type B DTC. A DTC only appears on the I/M System Status display when the DTC becomes a MIL illuminating DTC. This occurs on the second failure of a type B DTC. A first failure of a type B DTC will not allow the I/M System Status to update to YES. Refer to Diagnostic Aids.
- 4: This step helps identify any unique or unusual criteria required to run the diagnostic test in the event the universal set procedure does not. This information is located in the service information under Conditions for Running the DTC.
- 5: The I/M System Status only reports on whether or not a diagnostic test has run, not the outcome of the test. If any emission related DTC sets after the tests are complete, the DTC will require diagnosis.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 | Did you perform the Inspection/Maintenance (I/M) System Check? | Go to Step 2 | Go to Inspection/Maintenance (I/M) System Check | |
| 2 | Ensure the vehicle is within the Conditions for Running specified in the supporting text. Set the vehicle parking brake. Verify the transmission is in Park for automatic transmissions and Neutral for manual transmissions. Turn OFF all of the accessories, e.g., A/C, blower fan, etc. Start the engine, and allow the engine to idle. Allow the engine to idle for the specified time or until the I/M System Status indicator updates to YES. Did the Misfire Monitoring System Status update to YES? | 2 minutes | Go to Step 5 | Go to Step 3 |
| 3 | Observe the DTC information with a scan tool. Does the scan tool indicate any failed DTCs? | Go to Diagnostic Trouble Code (DTC) List | Go to Step 4 | |
| 4 | Refer to the Inspection/Maintenance (I/M) System DTC Table to determine which DTCs are required to run in order to complete this test. Observe the Not Ran Since Code Cleared parameter with a scan tool. Determine which of the DTCs required for a YES status has not run. Enter the DTC number in the Specific DTC menu of the scan tool. Operate the vehicle within the Conditions for Running the DTC, located in the supporting text for the diagnostic table of the DTC. Repeat the procedure until the scan tool indicates the diagnostic test has run. Repeat steps 4-6 for any additional required DTCs that have not run. Observe the I/M System Status with a scan tool. Did the Misfire Monitoring System Status update to YES? | Go to Step 5 | Go to Diagnostic Aids | |
| 5 | Observe the Emission Related DTC portion of the I/M System Status with a scan tool. Does the scan tool indicate any Emission Related DTCs set? | Go to Diagnostic Trouble Code (DTC) List | System OK |
Inspection/Maintenance (I/M) Misfire Monitoring System Set Procedure
The purpose of this test is to satisfy the enable criteria necessary to execute I/M readiness diagnostic tests for the Component Monitoring System. The test may be used to set the I/M System Status to YES. Ensure that the vehicle meets the requirements in Conditions for Running before performing this test. Failure to meet the necessary requirements may produce inaccurate test results.
The numbers below refer to the step numbers on the diagnostic table.
- 1: Ensure that you perform the I/M System Check before performing this test. Failure to do so may result in difficulty updating the status to YES.
- 3: This step identifies a first failure of a type B DTC. A DTC only appears on the I/M System Status display when the DTC becomes a MIL illuminating DTC. This occurs on the second failure of a type B DTC. A first failure of a type B DTC will not allow the I/M System Status to update to YES. Refer to Diagnostic Aids.
- 4: This step helps identify any unique or any unusual criteria required to run the diagnostic test in the event the universal set procedure does not. This information is located in the service information under Conditions for Running the DTC.
- 5: The I/M System Status only reports on whether or not a diagnostic test has run, not the outcome of the test. If any Emission Related DTC sets after the tests are complete, the DTC will require diagnosis.
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Did you perform the Inspection/Maintenance (I/M) System Check? | Go to Step 2 | Go to Inspection/Maintenance (I/M) System Check |
| 2 | Ensure the vehicle is within the Conditions for Running specified in the supporting text. Turn OFF all of the accessories, e.g., A/C, blower fan, etc. Start the engine, and allow the engine to idle for 2 minutes. CAUTION: Refer to Road Test Caution in Cautions and Notices. IMPORTANT: In order for this test to run, the vehicle must operate in the following conditions: Acceleration at part throttle to 80 km/h (50 mph) with this speed maintained until the engine reaches operating temperature. This may be up to 10 minutes depending on the start up coolant temperature. Continue the operating conditions for an additional 3 minutes after the engine reaches operating temperature. After the specified time has elapsed, vehicle requires acceleration at 75 percent throttle until a speed of 110 km/h (68 mph) is attained. Review the I/M System Status display with a scan tool. Did the Component Monitoring System Status update to YES? | Go to Step 5 | Go to Step 3 |
| 3 | Observe the DTC Information with a scan tool. Does the scan tool indicate any failed DTCs? | Go to Diagnostic Trouble Code (DTC) List | Go to Step 4 |
| 4 | Refer to the Inspection/Maintenance (I/M) System DTC Table to determine which DTCs are required to run in order to complete this test. Observe the Not Ran Since Code Cleared parameter with a scan tool. Determine which of the DTCs required for a YES status has not run. Enter the DTC number in the Specific DTC menu of the scan tool. Operate the vehicle within the Conditions for Running the DTC, located in the supporting text for the diagnostic table of the DTC. Repeat the procedure until the scan tool indicates the diagnostic test has run. Repeat steps 4-6 for any additional required DTCs that have not run. Observe the I/M System Status with a scan tool. Did the Component Monitoring System Status update to YES? | Go to Step 5 | Go to Diagnostic Aids |
| 5 | Observe the Emission Related DTC portion of the I/M System Status with a scan tool. Does the scan tool indicate any Emission Related DTCs set? | Go to Diagnostic Trouble Code (DTC) List | System OK |
| CAUTION |
|---|
| Refer to Road Test Caution in Cautions and Notices. |
| IMPORTANT |
|---|
| In order for this test to run, the vehicle must operate in the following conditions |
Inspection/Maintenance (I/M) Component Monitoring System Set Procedure
The number below refers to the step number on the diagnostic table.
- 7: This steps checks for a thermostatic switch that completes the circuit.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Engine Controls Schematics | ||||
| 1 | Does the Water In Fuel lamp operating properly? | Go to Step 2 | Go to Water-in-Fuel Lamp Always On in Instrument Panel, Gages, and Console | |
| 2 | Disconnect the fuel heater harness connector from the top of the fuel filter/heater element housing. Turn ON the ignition with the engine OFF. Probe the fuel heater ignition 1 voltage circuit with a test lamp connected to a good ground. Refer to Troubleshooting with a Test Lamp in Wiring Systems. Does the test lamp illuminate? | Go to Step 3 | Go to Step 5 | |
| 3 | Probe the fuel heater ground circuit at the fuel filter/heater element housing with a test lamp connected to B+. Refer to Troubleshooting with a Test Lamp in Wiring Systems. Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 | |
| 4 | Remove the fuel filter from the fuel filter/heater element housing. Test the ignition 1 voltage circuit and the ground circuit for an open in the fuel filter/heater element housing. Refer to Troubleshooting with a Digital Multimeter in Wiring Systems. Did either circuit test open? | Go to Step 11 | Go to Step 7 | |
| 5 | Is the fuel HT fuse open? | Go to Step 6 | Go to Step 8 | |
| 6 | Disconnect the intake air heater harness connector. Probe the ignition 1 voltage circuit with a test lamp connected to B+. Refer to Troubleshooting with a Test Lamp in Wiring Systems. Does the test lamp illuminate? | Go to Step 9 | Go to Step 7 | |
| 7 | Remove the fuel filter/heater element housing from the vehicle. Connect the ignition 1 voltage circuit of the fuel heater to battery voltage source and connect the ground circuit of the fuel heater to the ground of the voltage source. Cool the sensor part of the fuel heater with ice. Observe the heating element. Does the thermostatic switch turn ON when the temperature is within the specified range? | 8.4 to +15.4° C (+16.9 to +59.8° F) | Go to Step 13 | Go to Step 12 |
| 8 | Repair the open in the ignition 1 voltage circuit between the fuel filter/heater element housing and the Fuse. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 14 | ||
| 9 | Repair the short to ground on the ignition 1 voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 14 | ||
| 10 | Repair the open in the ground circuit between the fuel filter/heater element housing and chassis ground. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 14 | ||
| 11 | Replace the fuel filter/heater element housing. Refer to Fuel Filter/Heater Element Housing Replacement . Did you complete the replacement? | Go to Step 14 | ||
| 12 | Replace the fuel heater. Refer to Fuel Filter/Heater Element Housing Replacement . Did you complete the replacement? | Go to Step 14 | ||
| 13 | Replace the intake air heater relay. Refer to Intake Air Heater (IAH) Relay Replacement (Federal Emissions) or Intake Air Heater (IAH) Relay Replacement (California Emissions) . Did you complete the replacement? | Go to Step 14 | ||
| 14 | Operate the vehicle under which the problem was noted. Does the system operate properly? | System OK | Go to Step 1 | |
Fuel Heater Inoperative
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step checks for a fuel heater that is stuck ON.
- 3: This steps checks for a thermostatic switch that completes the circuit.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Engine Controls Schematics | ||||
| 1 | Does the Water In Fuel lamp operating properly? | Go to Step 2 | Go to Water-in-Fuel Lamp Always On in Instrument Panel, Gages, and Console | |
| 2 | Disconnect the fuel heater connector and remove the fuel heater from the filter housing. Refer to Fuel Filter/Heater Element Housing Replacement . With the fuel heater at room temperature, connect the ignition 1 voltage circuit of the fuel heater to B+ and connect ground circuit of the fuel heater to ground. Observe the heater element. Does heat occur? | Go to Step 4 | Go to Step 3 | |
| 3 | Remove the fuel filter/heater element housing from the vehicle. Connect the ignition 1 voltage circuit of the fuel heater to battery voltage source and connect the ground circuit of the fuel heater to the ground of the voltage source. Cool the sensor part of the fuel heater with ice. Observe the heating element. Does the thermostatic switch turn ON when the temperature is within the specified range? | 8.4 to +15.4° C (+16.9 to +59.8° F) | Go to Step 5 | Go to Step 4 |
| 4 | Replace the fuel heater. Refer to Fuel Filter/Heater Element Housing Replacement . Did you complete the replacement? | Go to Step 5 | ||
| 5 | Operate the vehicle under which the problem was noted. Does the system operate properly? | System OK | Go to Step 1 | |
Fuel Heater Always On
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step will make sure there are no other DTCs stored that will affect the operation of the glow plug system.
- 3: This step will check each glow plug for an open.
- 4: This step will check each glow plug feed circuit for an open.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views | |||
| 1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | Go to Diagnostic System Check - Engine Controls |
| 2 | Are DTCs P0117, P0118, P0380 stored as history or current codes? | Go to Diagnostic Trouble Code (DTC) List | Go to Step 3 |
| 3 | Turn OFF the ignition. Disconnect all the glow plugs. With a test lamp connected to battery voltage, probe the spade terminal on each glow plug. Do all glow plugs illuminate the test lamp? | Go to Step 4 | Go to Step 9 |
| 4 | Turn ON the ignition, with the engine OFF. Verify the glow plugs are still disconnected. Probe each glow plug supply voltage circuit with a test lamp connected to ground. Refer to Troubleshooting with a Test Lamp in Wiring Systems. With a scan tool, command the glow plugs ON. Does each circuit illuminate the test lamp? | Go to Step 5 | Go to Step 10 |
| 5 | Does the test lamp illuminate all the time for each glow plug terminal, even when the glow plugs are not commanded ON? | Go to Step 6 | Go to Step 11 |
| 6 | Disconnect the glow plug supply voltage connection from the glow plug relay. Probe each glow plug terminal with a test lamp connected to ground. Does the test lamp illuminate for all terminals? | Go to Step 7 | Go to Step 8 |
| 7 | Repair the short to voltage on the glow plug supply voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 11 | |
| 8 | Replace the glow plug relay/controller. Refer to Glow Plug Relay Replacement (Federal Emissions) or Glow Plug Relay Replacement (California Emissions) . Did you complete the replacement? | Go to Step 11 | |
| 9 | Replace all glow plugs that do not turn ON the test lamp. Refer to Glow Plug Replacement - Bank 1 or Glow Plug Replacement - Bank 2 . Did you complete the replacement? | Go to Step 11 | |
| 10 | Repair open in each circuit that does not turn ON the test lamp. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 11 | |
| 11 | Operate vehicle within the conditions under which system fault was noted. Does the system operate properly? | System OK | Go to Step 1 |
Glow Plug System Diagnosis
See also:
• Power and Grounding Component Views