2008/08/04 Caterpillar

Off-Highway Truck:

797 (S/N: 5YW1-UP)

Off-Highway Truck/Tractor:

797B (S/N: JSM1-369)

ReferenceSpecial Instruction, REHS3681, "Procedure To Rewire The Power Wire Circuit"

A new special instruction is available. The special instruction provides a procedure to separate the power for the cab and the power for the ECM "ignition on" from the chassis instrument power on the 797 and the 797B Off Highway Trucks. This is accomplished by separating the wire 113 junction blocks in order to place the wires for the cab and the wires for the engine "ignition on" into one junction block. The wires for the chassis instruments will be placed into another junction block. The wires for the cab and the wires for the ECM will be connected to the coil side of the main power relay. This update is effective back to the beginning of production of the above listed machines. This update became effective in production with the machine JSM370-UP.

For the complete list of needed parts and the correct procedure to update the cab wiring group, refer to Special Instruction, REHS3681, "Procedure To Rewire The Power Wire Circuit".