Modulating Valve Connectors May Not Be Fully Seated Caterpillar

Modulating Valve Connectors May Not Be Fully Seated

Usage:

WHEEL LOADERS

INTEGRATED TOOL CARRIERS

WHEEL TRACTORS

LANDFILL COMPACTORS

TRACK-TYPE TRACTORS

PIPELAYER

ARTICULATED TRUCKS

WHEEL SKIDDERS

OFF-HIGHWAY TRUCKS

950G (4BS1-Up, 3JW1-Up, 2JS1-Up, 5FW1-Up, 6NS1-Up, 5MW1-Up, 8JW1-Up),
962G (5AS1-Up, 4PW1-Up, 3BS1-Up, 7BW1-Up, 5RS1-Up, 6HW1-Up, 6EW1-Up, BDP1-Up),
966G (3ZS1-Up, 3SW1-Up, 9RS1-Up, 3PW1-Up, 8XW1-Up, AAH1-Up),
972G (4WW1-Up, 7LS1-Up, 1EW1-Up, 6AW1-Up, 9GW1-Up, AAW1-Up),
988G (2TW1-Up) WHEEL LOADERS;
IT62G (6PS1-Up, AKP1-Up) INTEGRATED TOOL CARRIERS;
834G (6GZ1-Up) WHEEL TRACTORS;
836G (7MZ1-Up) LANDFILL COMPACTORS;
D5M (3CR1-Up5ES1-Up, 6AS1-Up, 6GN1-Up, 7LR1-Up),
D6M (3WM1-Up, 4HS1-Up, 4JN1-Up, 5NR1-Up, 6LR1-Up),
D6R (1RW1-Up, 2HM1-Up, 2YN1-Up, 3ZN1-Up, 5LN1-Up, 4FM1-Up, 4HN1-Up, 4JR1-Up, 4MN1-Up, 4TR1-Up, 4WR1-Up, 5PR1-Up, 5RR1-Up,6FR1-Up, 6GR1-Up, 6HR1-Up, 6MR1-Up, 6JN1-Up, 7AR1-Up, 7DR1-Up, 7GR1-Up, 7KN1-Up, 8LN1-Up, 8TM1-Up, 8XN1-Up, 9MN1-Up, 9BM1-Up, 9PN1-Up, 9ZS1-Up) D7R (2EN1-Up, 2HR1-Up, 3DN1-Up, 3ZR1-Up, 4SR1-Up, 5MR1-Up, 6ER1-Up, 9HM1-Up),
D8RII (6YZ1-Up) TRACK-TYPE TRACTORS;
572R (2HZ1-Up, AAC1-Up) PIPELAYERS;
725 (AFX1-Up, 730 AGF1-Up) ARTICULATED TRUCKS;
525B (3KZ1-Up),
535B (AAE1-Up),
545 (2FZ1-Up) WHEEL SKIDDERS;
797 (5YW1-Up) OFF-HIGHWAY TRUCKS

Problem:

There is a possibility that some machines with 160-8408, 170-0761, 171-0890,or 171-1008 Modulating Valves may have a connector plug that is not fully seated into the receptacle on the valve coil which could cause intermittent open circuit faults. Additionally, if a connector is not fully seated, the latch on the plug portion of the connector (part of the wiring harness) could take a set and not be capable of locking the two halves of the connector together.

The connector, which is part of the coil on the 160-8408, 170-0761, 171-0890, or 171-1008 Modulating Valves, has a round button of soft rubber in the end of the body with two smaller protrusions of rubber at each of the pins. When the harness connector is plugged into the connector on the coil, some resistance is felt when the connector contacts the rubber JUST BEFORE the lock actually clicks into place. If the lock is not fully engaged and the connection is exposed to heat for a period of time, the lock will take a set which prevents the connector from ever being capable of locking.

The 160-8408 Modulating valve is used in the transmissions on all of the listed machines except the 797 Off Highway Truck, 525B, 535B, and the 545 Wheel Skidders. The 160-8408 Modulating valve is used to control the torque converter lockup clutch on the 525B, 535B, and the 545 Wheel Skidders. The 170-0761 Modulating valve is used to control the torque converter lockup clutch on the 988G, 834G, and the 836G. The 171-0890 and the 171-1008 Modulating Valves are used in the transmission control of the 797 Off Highway Truck.

Solution:

If a machine is experiencing open circuit faults for a clutch equipped with a 160-8408, 170-0761, 171-0890, and 171-1008 Modulating Valve, check the connector to be sure it is fully seated and the locking tab is up and latched. If a connector is found where the locking tab is not latched, it is recommended that the connector body of the harness (which includes the locking tab) be replaced be a new 155-2270 Plug kit.