System Operation Description:
Use this procedure to troubleshoot any suspect problems with the Injection Actuation Pressure Control Valve (IAPCV). Use this procedure if the diagnostic code or the event code in Table 1 is active or easily repeated.
Diagnostic Codes Table     | ||
---|---|---|
Description     | Conditions which Generate this Code     | System Response     |
42-5 Injector Actuation Valve current below normal     | The Electronic Control Module (ECM) detects a current in the circuit for the Injection Actuation Pressure Control Valve (IAPCV) that is below the minimum threshold. The ECM has been powered for three seconds.     |
The engine may begin to misfire and/or shutdown. The engine may experience reduced speed (rpm) and/or low power. The code is logged.     |
42-6 Injector Actuation Valve current above normal     | The ECM detects a current in the circuit for the IAPCV that is above the maximum threshold. The ECM has been powered for three seconds.     |
The engine may begin to misfire and/or shutdown. The engine may experience reduced speed (rpm) and/or low power. The code is logged.     |
42-11 Injector Actuation Valve other failure mode     | The Electronic Control Module (ECM) detects an open circuit and current in the circuit for the IAPCV that is greater than 0.2 amps.     | The current for the IAPCV is set to 0.0 amps for 15 mSec. The code is logged.     |
164-0 Injector Actuation Pressure high - most severe (3)     | The ECM detects injection actuation pressure that is above 24 MPa (3481 psi) for one second. The ECM has been powered for three seconds.     |
The code is logged. The fuel limit is set to a predetermined value.     |
164-11 Injector Actuation Pressure other failure mode     | The ECM detects desired injection actuation pressure that differs from actual injection actuation pressure by more than 1 MPa (145 psi) for one second or the ECM detects current to the IAPCV at the minimum or the maximum value for 0.5 seconds. The ECM has been powered for three seconds.     |
The code is logged. The injection actuation pressure is set to 12 MPa (1740.5 psi). The current to the IAPCV is set to 20 percent. The fuel limit is set to a predetermined value.     |
E164(1) High Injector Actuation Pressure     | The ECM detects injection actuation pressure that is above 24 MPa (3481 psi) for one second. The ECM has been powered for three seconds. The ECM has been powered for three seconds.     |
The code is logged. The fuel limit is set to a predetermined value.     |
The IAPCV regulates the high pressure oil system that drives the Hydraulic Electronic Unit Injectors (HEUI). The injection actuation pressure sensor monitors the pressure of the high pressure oil system. The ECM adjusts the pulse width modulated signal to the IAPCV in order to regulate the injection pressure. The IAPCV operates on a signal between 0 and 800 mA.
The ECM uses the following criteria in order to determine the desired injection actuation pressure:
- Fuel quality
- Injection timing
- Engine speed (rpm)
- Engine operating mode (cold mode, etc.)
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Illustration 1 | g01394156 |
Schematic for the injection actuation pressure control valve |
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Illustration 2 | g01408155 |
Component locations (1) Injection actuation pressure sensor (2) Injection actuation pressure control valve |
Test Step 1. Check for Active Diagnostic Codes
- Connect AVSpare Electronic Technician (ET) to the data link connector.
- Restore electrical power to the ECM.
- Start the engine.
- Observe the "Active Diagnostic" screen on Cat ET. Wait at least 30 seconds so that any codes may become active.
Expected Result:
One of the following diagnostic codes is present:
- 42-5
- 42-6
- 42-11
- 164-0
- 164-11
- E164(1)
Results:
- OK - One of the above codes is active. Proceed to Test Step 2.
- Not OK - Neither of the above codes are active. There may be a mechanical problem with the high pressure oil system.
Repair: If one of the above codes is logged and the engine is not running properly, refer to Troubleshooting, "Symptom Troubleshooting".If the engine is running properly at this time, there may be an intermittent problem in a harness or in an electrical connector that is causing the codes to be logged. Refer to Troubleshooting, "Electrical Connectors - Inspect".
STOP
Test Step 2. Inspect Electrical Connectors and Wiring
- Remove electrical power from the ECM.
- Thoroughly inspect the J1/P1 and thoroughly inspect the J2/P2 ECM connectors. Thoroughly inspect any connectors that are associated with the circuit for the IAPCV. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
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Illustration 3 | g01408183 |
ECM (3) J1/P1 connectors (4) J2/P2 connectors |
- Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the ether injection system.
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Illustration 4 | g01394746 |
P2 ECM connector (P2-29) IAPCV supply (P2-35) IAPCV return |
- Check the allen head screw on each ECM connector for the proper torque. Also check the allen head screw on the customer connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
- Check the harness and the wiring for abrasion and for pinch points from the ether injection solenoid to the ECM. Verify that all connections and grounds are tight and free of corrosion.
Expected Result:
All connectors, pins, and sockets are completely inserted and coupled. The harness and wiring are free of corrosion, of abrasions, and of pinch points. All connections and grounds are tight and free of corrosion.
Results:
- OK - The connectors and wiring appear to be OK. Proceed to Test Step 3.
- Not OK - The connectors and/or wiring are not OK.
Repair: Repair the circuit.Verify that the repair eliminates the problem.
STOP
Test Step 3. Check the Solenoid for an Internal Open or Short
- Disconnect the IAPCV connector.
- Measure the resistance between terminal 1 (IAPCV supply) and terminal 2 (IAPCV return) on the solenoid.
Expected Result:
The resistance is between 5 Ohms and 15 Ohms.
Results:
- OK - The resistance is between 5 Ohms and 15 Ohms. Proceed to Test Step 4.
- Not OK - The resistance is not between 5 Ohms and 15 Ohms. The IAPCV is faulty.
Repair: Replace the IAPCV.Verify that the repair eliminates the problem.
STOP
Test Step 4. Check for Shorts in the Harness
- Disconnect the J2/P2 ECM connector.
- Disconnect the IAPCV connector.
- Measure the resistance between P2-29 (IAPCV supply) and engine ground. Also, measure the resistance between P2-29 (IAPCV supply) and all the other pins on the J2/P2 ECM connector.
- Measure the resistance between P2-35 (IAPCV return) and engine ground. Also, measure the resistance between P2-35 (IAPCV return) and all the other pins on the J2/P2 ECM connector.
Expected Result:
All of the resistance measurements indicate an open circuit.
Results:
- OK - All of the resistance measurements indicate an open circuit. Proceed to Test Step 5.
- Not OK - A resistance measurement does not indicate an open circuit. There is a short in the wiring between the ECM and the IAPCV.
Repair: Repair the circuit.Verify that the repair eliminates the problem.
STOP
Test Step 5. Check for Open Circuits in the Harness
- Disconnect the J2/P2 connectors.
- Disconnect the IAPCV connector.
- Create a short circuit between terminal 1 and terminal 2 at the IAPCV connector.
- Measure the resistance between terminal locations P2-29 and P2-35 at the ECM connector.
- Return all connectors to the original configuration.
Expected Result:
The resistance does not indicate an open circuit.
Results:
- OK - The resistance does not indicate an open circuit. Proceed to Test Step 6.
- Not OK - The resistance indicates an open circuit. There is an open circuit in the wiring harness between the IAPCV and the ECM.
Repair: Repair the circuit.Verify that the repair eliminates the problem.
STOP
Test Step 6. Perform the "Injection Actuation Pressure Test"
- Reconnect all connectors.
- Connect Cat ET to the data link connector.
- Restore electrical power to the ECM.
- Start the engine.
- Select the "Injection Actuation Pressure Test" under the "Diagnostics" menu in Cat ET.
- Increase the desired injection actuation pressure to 21500 kPa (3118 psi). Observe the actual injection actuation pressure reading.
- Decrease the desired injection actuation pressure to 8000 kPa (1160 psi). Observe the actual injection actuation pressure reading.
Expected Result:
Actual injection actuation pressure is within 2000 kPa (290 psi) of the desired injection actuation pressure.
Results:
- OK - Actual injection actuation pressure is acceptable. The injection actuation pressure circuit is working properly.
Repair: Refer to Troubleshooting, "Electrical Connectors - Inspect" if the problem is intermittent.Verify that the repair eliminates the problem.
STOP
- Not OK - Actual injection actuation pressure is not acceptable. Proceed to Test Step 7.
Test Step 7. Temporarily Install a New IAPCV
- Remove electrical power from the ECM.
- Remove the IAPCV.
- Temporarily install a new IAPCV.
- Reconnect all connectors.
- Connect Cat ET to the data link connector.
- Start the engine.
- Select the "Injection Actuation Pressure Test" under the "Diagnostics" menu in Cat ET.
- Increase the desired injection actuation pressure to 21500 kPa (3118 psi). Observe the actual injection actuation pressure reading.
- Decrease the desired injection actuation pressure to 8000 kPa (1160 psi). Observe the actual injection actuation pressure reading.
Expected Result:
Actual injection actuation pressure is within 2000 kPa (290 psi) of the desired injection actuation pressure.
Results:
- OK - Actual injection actuation pressure is acceptable. The IAPCV was faulty.
Repair: Permanently install the new IAPCV.Verify that the repair eliminates the problem.
STOP
- Not OK - Actual injection actuation pressure is not acceptable. Proceed to Test Step 8.
Test Step 8. Check the ECM
- Remove electrical power from the ECM.
- Disconnect the J2/P2 ECM connector.
- Fabricate two jumper wires that are long enough to be used to measure the supply voltage at the ECM connectors. Crimp connector sockets to one end of each jumper wire.
- Remove the wires from terminal locations P2-35 (IAPCV return) and P2-29 (IAPCV supply). Install a jumper wire into each of these terminal locations.
- Reconnect the J2/P2 ECM connector.
- Connect Cat ET to the data link connector.
- Restore electrical power to the ECM.
- Access the "Injection Actuation Pressure Driver Test" that is under the "Diagnostics" menu.
- Connect a circuit test light to P2-29 (IAPCV supply) and P2-35 (IAPCV return).
- Start the "Injection Actuation Pressure Driver Test". Observe the circuit test light.
Expected Result:
The circuit test light illuminates when the test is active.
Note: The presence of the circuit test light may cause a -5 Injector Actuation Valve current below normal or a -6 Injector Actuation Valve current above normal to become active.
Results:
- OK - The circuit test light illuminates when the test is active. There may be a mechanical problem with the engine.
Repair: Repair the problem. Refer to the appropriate topic in Troubleshooting, "Sympton Troubleshooting".Verify that the repair eliminates the problem.A 164-0 diagnostic code is active at this time. Refer to Troubleshooting, "Sensor Signal (Analog, Active) - Test".
STOP
- Not OK - The circuit test light does not illuminate when the test is active. The ECM is not controlling the IAPCV correctly.
Repair: Replace the ECM. Refer to Troubleshooting, "ECM - Replace" before replacing the ECM.Verify that the repair eliminates the problem.
STOP