EDGE GP 1247287 - Caterpillar

Illustration 1 g03367399Power to the VIMS module can fail due to an open circuit in the wire, a poor connection, or a failed fuse. A short or overloaded circuit can cause a fuse to fail.Test Step 1. CHECK THE ECM FOR POWER AND GROUNDOn the VIMS module, measure the voltage from pin 52 (wire 150-RD(Red)) to pin 65 (wire 201-BK(Black)) .Expected Result:The measured voltage is the same as the system voltage.Results:
YES - The measured voltage is the same as the system voltage.STOP
NO - The measured voltage is low. Proceed to Test Step 2.Test Step 2. CHECK THE FUSE OR CIRCUIT BREAKER
Check the ECM power supply circuit breaker CB1. Expected Result:The circuit breaker should be good.Results:
YES - The circuit breaker is good. Proceed to Test Step 3.
NO - The circuit breaker has failed.Repair: Replace the circuit breaker. Observe the machine for a recurrence of the problem. If the problem persists, the reason for the problem must be isolated and corrected.STOPTest Step 3. CHECK THE POWER WIRE TO THE ECM
Turn the battery disconnect switch to the OFF position.
Turn the key start switch to the OFF position.
Measure the resistance of the VIMS module power wire 150-RD(Red) at the fuse and at pin 52 of the VIMS module connector . Expected Result:The resistance should be less than 5 ohms.Results:
YES - The resistance is less than 5 ohms. Proceed to Test Step 4.
NO - The resistance measurement is greater than 5 ohms. The wiring has an open circuit.Repair: Repair or replace the harness. STOPTest Step 4. CHECK THE ECM GROUND CONNECTIONS
Turn the battery disconnect switch to the OFF position.
Turn the key start switch to the OFF position.
Measure the resistance between contact 65 201-BK(Black) at the VIMS ECM connector and frame ground. Expected Result:The resistance should be less than 5 ohms.Results:
YES - The resistance is less than 5 ohms. The ECM may have failed, however, ECM failure is unlikely.Repair: Perform this procedure again. If the cause of the problem cannot be determined, contact your Cat dealer. If ECM replacement is required, see the Testing and Adjusting, "Electronic Control Module (ECM) - Replace" Section of this manual.STOP
NO - The resistance is greater than 5 ohms. The ground circuit has failed.Repair: Repair or replace the harness.STOP