SWITCH AS 2873838 - Caterpillar

Table 2
Continuity Checks and Results for the Engine Control Switch
Switch Position Terminal Locations Result
OFF/RESET P1-31 and P1-61 No continuity
P1-31 and P1-62
P1-31 and P1-64
AUTO P1-31 and P1-61 No continuity
P1-31 and P1-62
P1-31 and P1-64 Continuous
STOP P1-31 and P1-61 Continuous
P1-31 and P1-62 No continuity
P1-31 and P1-64
START P1-31 and P1-61 No continuity
P1-31 and P1-62 Continuous
P1-31 and P1-64 No continuity Connect the J1/P1 ECM connectors.Expected Result:Each of the continuity checks agree with the results that are given in the Table.Results:
OK - The continuity checks agree with the results that are given. There is not a problem with the engine control switch or the circuit for the switch. Proceed to Test Step 5.
Not OK - At least one of the continuity checks did not agree with the results that are given.Repair: There is a problem in the harness or in a connector that is for the engine control switch. The problem could be in the harness that is inside the terminal box for the ECM. There may be a problem with the engine control switch. Perform the necessary repairs. Replace parts, if necessary. Verify that the repair eliminates the original problem.STOPTest Step 5. Check for Keyswitch Power at the ECM Connector
Ensure that the engine will not crank during this procedure. Remove the pressurized air supply from the air start system. Purge any remaining pressurized air from the system.
Restore electrical power to the engine.
Use two 7X-1710 Multimeter Probes at the terminal locations of the P1 ECM connector