3126B Marine Engines Caterpillar

Use the following information to troubleshoot the system when the following diagnostic code is active:

• 164-02

Note: This procedure can be used to check the accuracy of the injection actuation pressure sensor against a pressure gauge.

The injection actuation pressure sensor measures the pressure of the oil in the high pressure oil manifold. The high pressure oil in the manifold is used to actuate the injectors and the high pressure oil is used to control the fuel injection pressure. The fuel injection pressure is based on inputs from the sensors. The inputs are used by the Electronic Control Module (ECM) for calculating the fuel injection pressure. The ECM uses the reading from the injection actuation pressure sensor in order to control the operation of the injection actuation pressure control valve.

Illustration 1	g01053316
Schematic

Illustration 2	g01056804

Test Step 1. Check for Active Diagnostic Codes

1. Connect the Caterpillar Electronic Technician (Cat ET) to the service tool connector.

2. Turn the keyswitch to the ON position.

   Note: If 164-02 is not active or logged, try to start the engine.

   Note: If a 164-03 or 164-04 diagnostic code is active, refer to Troubleshooting, "Engine Pressure Sensor Open or Short Circuit-Test".

Expected Result:

164-02 is active.

Results:

• OK - The diagnostic code is active. Proceed to Test Step 2.

• Not OK - Engine Will Not Start - The diagnostic code is not active and the engine will not start. Proceed to Test Step 2.

• Not OK - Engine Starts - The diagnostic code is not active and the engine will start. The system is operating correctly. Stop.

Test Step 2. Disconnect the Injection Actuation Pressure Sensor and Start the Engine

1. Turn the keyswitch to the OFF/RESET position.

2. Disconnect the J204/P204 injection actuation pressure sensor connector.

3. Try to start the engine.

Expected Result:

The engine starts.

Results:

• OK - The engine starts when the injection actuation pressure sensor is disconnected. Proceed to Test Step 3.

• Not OK - The engine will not start.

  Repair: Refer to Troubleshooting, "Engine Cranks but Will Not Start".

  Stop.

Test Step 3. Inspect Electrical Connectors and Wiring

1. Turn the keyswitch to the OFF/RESET position.

2. Thoroughly inspect the J204/P204 injection actuation pressure sensor connector and the J2/P2 ECM connector. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.

3. Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the injection actuation pressure sensor.

4. Check the ECM connector (allen head screw) for the proper torque of 6.0 N·m (55 lb in).

5. Check the harness and wiring for abrasion and for pinch points from the sensor back to the ECM.

Expected Result:

All connectors, pins and sockets are completely coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion and of pinch points.

Results:

• OK - The wiring and the connectors appear to be OK. Proceed to Test Step 4.

• Not OK - There is a problem with the wiring and/or the connectors.

  Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem.

  Stop.

Test Step 4. Check the Status of the Sensor while the Engine is Off

1. Turn the keyswitch to the ON position.

2. Check the status of the injection actuation pressure on Cat ET.

   Note: The following diagnostic codes will cause the status for the injection actuation pressure to default to 17500 kPa (2538 psi).

   • 164-03

   • 164-04

   • 262-03

   • 262-04

Expected Result:

The status for the injection actuation pressure is 0 kPa (0 psi).

Results:

• OK - The status for the injection actuation pressure is 0 kPa (0 psi). Proceed to Test Step 6.

• Not OK - The status for the injection actuation pressure is not 0 kPa (0 psi). Proceed to Test Step 5.

Test Step 5. Check the Voltage Supply to the Injection Actuation Pressure Sensor

1. Turn the keyswitch to the OFF/RESET position.

2. Disconnect the J204/P204 injection actuation pressure sensor connector from the engine harness.

3. Connect a 3-terminal breakout T to the J204 connector (harness side) only.

4. Turn the keyswitch to the ON position.

5. Measure the voltage between terminal A and terminal B at the breakout T.

Expected Result:

The voltage reading is between 4.8 VDC and 5.2 VDC.

Results:

• OK - The sensor is receiving the proper supply voltage. Proceed to Test Step 6.

• Not OK - The sensor is not receiving the correct supply voltage.

  Repair: Refer to Troubleshooting, " Analog Sensor Supply Circuit - Test".

  Stop.

Test Step 6. Compare the Sensor Reading from Cat ET to a Pressure Gauge

Show/hide table

Hot oil and hot components can cause personal injury. Do not allow hot oil or hot components to contact the skin.

1. Turn the keyswitch to the OFF/RESET position.

2. Install a 8T-0852 Pressure Gauge (0 to 40,000 kPa (0 to 5,800 psi)) in one of the unused oil ports in the high pressure oil rail on the left side of the cylinder head.

3. Start the engine.

4. Go to the "Injection Actuation Pressure Test" in the Diagnostic Menu on Cat ET.

5. Start the test and monitor the status of the injection actuation pressure on Cat ET. Compare the pressure reading from Cat ET to the pressure reading on the 8T-0852 Pressure Gauge. Perform a comparison of the two different pressure indicators at varying engine rpm.

   Note: Use the table below for the approximate range of the injection actuation pressure sensor. Compare the 8T-0852 Pressure Gauge pressure reading to the chart.

   Show/hide table

   Table 1

   Pressure Reading from Service Tool	Range of Readings from Pressure Gauge
   6000 kPa (870 psi)	4000-7800 kPa (580-1130 psi)
   10000 kPa (1450 psi)	8000-11800 kPa (1160-1710 psi)
   15000 kPa (2175 psi)	13000-16800 kPa (1885-2435 psi)
   23000 kPa (3336 psi)	21000-24800 kPa (3045-3595 psi)

Expected Result:

Cat ET and the pressure gauge readings agree.

Results:

• OK - The injection actuation pressure sensor and the ECM are working properly.

  Repair: Refer to the appropriate topic for the symptoms in Troubleshooting, "Troubleshooting without a Diagnostic Code".

  Stop.

• Not OK - The readings do not agree.

  Repair: Temporarily replace the injection actuation pressure sensor and repeat the test. Replace the injection actuation pressure sensor if this corrects the problem. If this does not correct the problem, then the pressure gauge is faulty.

  Stop.