BOLT 8T7547 - Caterpillar

System Operation Description:Engine sensors provide various signals to the engine's Electronic Control Module (ECM). These sensors receive a regulated voltage from the engine ECM. Analog sensors receive 5.0 0.2 VDC and digital sensors receive 8.0 0.4 VDC.The ECM performs an automatic calibration of these sensors whenever power is first applied to the engine ECM and the engine has been off for at least five seconds. During an automatic calibration, the ECM calibrates pressure sensors against the atmospheric pressure sensor and an acceptable offset pressure range.
Illustration 1 g01017750Test Step 1. Check for Connector Damage.
Turn the ECS to the OFF/RESET position.
Turn the battery disconnect switch to the OFF position.
Thoroughly inspect the ECM connectors J1/P1 and J2/P2. Inspect all of the other connectors. Refer to the diagnostic functional test Troubleshooting, "Inspecting Electrical Connectors" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the circuit.
Check the allen head screw on each ECM connector for the proper torque. Refer to Troubleshooting, "Inspecting Electrical Connectors" for the correct torque values.
Check the harness and the wiring for abrasion and for pinch points. Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The connectors and wiring are OK. Proceed to Test Step 2.
Not OK - The connectors and/or wiring are not OK.Repair: Repair the connectors or wiring and/or replace the connectors or wiring.STOPTest Step 2. Check for "ACTIVE" Diagnostic Codes.
Connect the Caterpillar Electronic Technician (ET) to the ECM through the service tool connector.
Turn the battery disconnect switch to the ON position.
Turn the ECS to the STOP position. The engine should be off.
Wait for 15 seconds for the CID-FMI. Expected Result:Determine the failure mode identifier (FMI). Determine if the diagnostic codes 262-03 5 Volt Sensor DC Power Supply short to +batt or 262-04 5 Volt Sensor DC Power Supply short to ground are present. Determine if the diagnostic codes 263-03 Digital Sensor Supply short to +batt or 263-04 Digital Sensor Supply short to ground are present.Results:
FMI 03 - A diagnostic code with a FMI of 03 is present. Proceed to Test Step 3.
FMI 04 - A diagnostic code with a FMI of 04 is present. Proceed to Test Step 4.
FMI 00 or 08 - A diagnostic code with a FMI of 00 or of 08 is present. Proceed to Test Step 11.
262-03 or 262-04 Active Code - A diagnostic code of 262-03 or of 262-04 is present.Repair: Perform the diagnostic functional test Troubleshooting, "Analog Sensor Supply".STOP
263-03 or 263-04 Active Code - A diagnostic code of 263-03 or 263-04 is present.Repair: Perform the diagnostic functional test Troubleshooting, "Digital Sensor Supply".STOPTest Step 3. Check the Sensor Supply Voltage at the Sensor Connector if the Diagnostic Code FMI-03 is Present.
Turn the ECS to the OFF/RESET position.
Disconnect the suspect sensor. Note: Disconnecting the sensor will generate an open circuit diagnostic code for any sensor that is disconnected. Troubleshoot the original