CONVERTER AS 7E9725 - Caterpillar

Operation Description:The ECM activates the start relay when the key start switch is in the START position. The ECM detects a failure in the circuit for the start relay and the electrical system. "Check the key start switch". See Troubleshooting, "Diagnostic Code List".Test Step 1. CHECK THE SUPPLY VOLTAGE FOR THE CIRCUIT
Remove the harness connector from the switch.
At the harness connector of the keyswitch, measure the voltage between pin 3 (wire307-OR) and the frame ground location.Expected Result:The voltage measurement is equal to the system voltage of the machine.Results:
OK - The voltage measurement is equal to the system voltage of the machine. Proceed to Test Step 2.
NOT OK - The voltage measurement is less than the system voltage of the machine.Repair: Check the continuity of fuse G11 associated with the keyswitch. Replace the fuse if the fuse fails the continuity check. Check the voltage at pin 3 of the harness connector after the fuse has been checkedSTOPTest Step 2. CHECK THE KEY START SWITCH IN THE START POSITION.
Disconnect the ECM from the machine harness.
Turn and hold the key start switch in the START position.
At the machine harness connector for the ECM, measure the voltage between contact J2-1 (wire 307-OR) and contact J1-13 (wire 202-BK) (ground).Expected Result:The +battery voltage should be present.Results:
YES - The +battery voltage is present. Proceed to Test Step 3.
NO - The +battery voltage is NOT present. The key start switch or the machine harness (wire 307-OR) has failed. Check the key start switch and the machine harness.Repair: If necessary, replace the key start switch and/or the machine harness.STOPTest Step 3. CHECK THE KEY START SWITCH IN THE OFF POSITION.
The ECM remains disconnected from the machine harness.
Turn the key start switch to the OFF position.
At the machine harness connector for the ECM, measure the voltage between contact J2-1 (wire 307-OR) and contact J1-13 (wire 202-BK) (ground).Expected Result:The +battery voltage should be present.Results:
YES - The +battery voltage is present. The key start switch or the machine harness (wire 307-OR) has failed. Check the key start switch and the machine harness.Repair: If necessary, replace the key start switch and/or the machine harness.STOP
NO - The +battery voltage is NOT present. The harness circuit operates correctly. The ECM has failed. Repair: Ensure that you have the latest version of software for your specific machine and ECM. Refer to the Testing and Adjusting, "Electronic Control Module (ECM) - Flash Program" section of this manual for the correct procedure.Turn the disconnect switch to the ON position. Turn the key switch to the ON position and verify that reflashing the ECM has cleared the problem.If the diagnostic code is still present after flashing the latest software to your ECM, contact the Technical Communicator for your dealership for possible consultation with Caterpillar.This consultation may greatly reduce repair time. If the ECM requires replacement, see Testing and Adjusting, "Electronic Control Module (ECM) - Replace".STOP