INSTALLATION AR-ENGINE 4935857 - Caterpillar

Illustration 4 g01571794
Two cab bulkhead 70 contact connectors that pass many of the Machine ECM and Implement ECM circuits through the cab wall - these connectors provide a good point to check pass through circuits such as the HV Present Lamp power circuit in order to determine if a problem is in the cab harness or the chassis harness (1) CH-C10 Upper 70 contact connector (Implement ECM circuits) (2) CH-C2 Lower 70 contact connector (Machine ECM circuits)The key start switch remains in the OFF position. The disconnect switch remains in the OFF position.
At the HV Present Lamp, disconnect the machine harness connector for the LED lamp.
Turn the disconnect switch to the ON position.
At the disconnected machine harness connector for the lamp, use a multimeter to check the DC voltage between contact 1 (wire 102-RD) and a good frame ground contact point.Expected Result:The voltage measurement between the power circuit for the lamp and frame ground is at the +battery voltage level that was observed for the voltage check at the fuse panel contact.Results:
YES - The voltage measurement between the power circuit for the lamp and frame ground is at the +battery voltage level that was observed for the voltage check at the fuse panel contact. The power circuit for the HV Present Lamp is OK. Proceed to Test Step 4.
NO - The voltage measurement between the power circuit for the lamp and frame ground is not indicating the same +battery voltage level that was observed for the voltage check at the fuse panel contact. Repair: There is a problem in the power circuit (wire 102-RD) in the machine harness.Turn OFF the disconnect switch. Check the continuity of the 102-RD circuit wire between the lamp connector and the fuse panel.Refer to the complete machine Electrical System Schematic. Check the connections that are in the power circuit for open circuits or poor connections.The power circuit passes through the cab wall in the 70 pin CH-C10 connector that is located on the outside of the cab on the lower right hand side. Use the machine schematic to find the contact for the 102-RD power circuit wire on this connector.Disconnect the chassis side of the 70 pin CH-C10 connector on the outside of the cab. Check the lamp power circuit contacts for any problems at this connector.If no problem are found at the power circuit contacts for the 70 pin CH-C10 connector, check the other connectors in the circuit in the same manner. Verify that power is at the contacts of the connectors as they are checked.Repair the machine harness or replace the machine harness.STOPTest Step 4. CHECK THE APC SINKING DRIVER CIRCUIT FOR THE LAMPThe key start switch remains in the OFF position. The disconnect switch remains in the ON position.The machine harness connector for the HV Present Lamp remains disconnected.
At the disconnected machine harness connector for the lamp, obtain a segment of jumper wire that will reach back to the APC. Connect one end of the jumper wire to contact 2. (wire