PIPE 2964744 - Caterpillar

Illustration 7 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 allen head screw on each ECM connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
Check the allen head screw on the customer connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque value.
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
262-04
100-10
102-10
1785-10Expected Result:One of the above codes is active.Results:
Active 03 code - An 03 diagnostic code is active. Proceed to Test Step 3.
Active 04 code - An 04 diagnostic code is active. Proceed to Test Step 4.
Active 10 code - A 10 diagnostic code is active. Proceed to Test Step 3.
No active codes - None of the above codes are active.Repair: If any of the above codes are logged and the engine is not running properly, refer to Troubleshooting, "Troubleshooting Without a Diagnostic Code".If the engine is running properly at this time, there may be an intermittent problem in a harness that is causing the codes to be logged. Refer to Troubleshooting, "Electrical Connectors - Inspect".STOPTest Step 3. Check the Voltage on the +5 V Supply Wire
Turn the keyswitch to the OFF position.
Disconnect the harness connectors for the following sensors:
Intake manifold (Boost) pressure sensor
Atmospheric pressure sensor
Fuel pressure sensor
Engine oil pressure sensor
Auxiliary pressure sensor (if equipped)
Turn the keyswitch to the ON position.Note: Be sure to wiggle the harness during the following measurements in order to reveal an intermittent condition.
Measure the voltage between terminals A and B at each sensor connector on the engine harness.Expected Result:Each voltage measurement is 5.0 0.2 VDC.Results:
OK - Each voltage measurement is 5.0 0.2 VDC.Repair: Connect all of the sensor connectors. Clear all diagnostic codes. Check for active diagnostic codes. If the problem is intermittent, refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Yes - The voltage measurement is 5.0 0.2 VDC. The 5 volt supply is present at the harness connector for the suspect sensor. However, there is an active 10