STRAINER ASSEM. 3D6678 - Caterpillar

System Operation Description:The Electronic Control Module (ECM) creates a regulated voltage of 5.0 0.2 VDC that is supplied to terminal A of the harness connectors for these sensors:
Injection actuation pressure sensor
Boost pressure sensor
Atmospheric pressure sensor
Fuel pressure sensor
Engine oil pressure sensor
Auxiliary pressure sensorThis procedure covers the following diagnostic codes:
262-03 5 Volt Sensor DC Power Supply short to +batt
262-04 5 Volt Sensor DC Power Supply short to groundA +5 V diagnostic code is probably caused by a short circuit to ground or a short circuit to another voltage source in the harness. The next likely cause is a problem with a sensor. The least likely cause is a problem with the ECM.
Illustration 1 g01128578
Schematic for the 5 volt supplyTest Step 1. Inspect the Electrical Connectors and the Wiring
Turn the keyswitch to the OFF position.
Illustration 2 g01128582
Left side view (1) Injection actuation pressure sensor (2) Boost pressure sensor (3) Atmospheric pressure sensor (4) Fuel pressure sensor (5) Engine oil pressure sensor (6) J2/P2 ECM connector (7) J1/P1 ECM connector
Thoroughly inspect connectors (6) and (7). Thoroughly inspect the connectors for each pressure sensor. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Illustration 3 g01128590
P2 terminals that are associated with the 5 volt supply for the pressure sensors (P2-2) +5 VDC (P2-3) Return
Illustration 4 g01128693
P1 terminals that are associated with the 5 volt supply for the pressure sensors (P1-2) +5 VDC (P1-3) Return
Illustration 5 g01128703
J61/P61 terminals that are associated with the 5 volt supply for the pressure sensors (14) +5 VDC (15) Return
Illustration 6 g01123211
Connectors for the sensors (A) Supply (B) Return (C) Signal
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the pressure sensor supply.
Check the torque of the allen head screw on the ECM connectors and the customer connector. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
Check the harness and the wiring for abrasion and for pinch points from each sensor back to the ECM.Expected Result:All of the 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 harness and connectors appear to be OK. Proceed to Test Step 2.
Not OK - The connectors and/or wiring are not OK.Repair: Repair the wiring and/or the connectors. Replace parts, if necessary. 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.STOPTest Step 2. Check for Active Diagnostic Codes
Connect the Caterpillar Electronic Technician (ET) to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools".
Turn the keyswitch to the ON position.
Observe the "Active Diagnostic" screen on Cat ET. Wait at least 15 seconds so that any codes may become active. Look for these codes:
262-03
262-04Expected Result:One of the above codes is active.Results:
Active 262-03 code - An 262-03 diagnostic code is active. Proceed to Test Step 3.
Active 262-04 code - An 262-04 diagnostic code is active. Proceed to Test Step 4.
No active codes - None of the above codes are