Medium and Heavy Trucks
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Hi my name is***** will be glad to try to help. That part number comes up as a gasket kit?
Either way, Test all your fuses for power on both sides with the key on, Check your relays by swapping with a known good one and test for power in each gear position to the transmission solenoids and in and out of the shift controller. Check the transmission neutralizer switch and circuit for continuity of the switch and wiring harness for damage or corrosion. Let me know the results.
System Operation Description:
The parking brake switch is an input to the direction lever. The parking brake relay is an input to the direction lever. When the parking brake is applied, the parking brake switch is open. The parking brake relay is not energized. Releasing the parking brake closes the parking brake switch. When the parking brake switch is closed, the parking brake relay is not energized. When the direction lever is placed in neutral, the parking brake relay is energized. The relay then remains energized. The position of the direction lever does not matter. The relay remains energized until the parking brake is applied. When the brake is applied,the parking brake switch opens. The parking brake relay is de-energized. The machine will not shift into gear unless the parking brake relay is energized.
Note: If shifting problems occur, the control module may not indicate a problem. Check the following items.
Test Step 1. CHECK THE CIRCUIT FOR PROPER OPERATION
When the parking brake is applied, the parking brake switch should be open. The parking brake lamp should be ON. The parking brake relay should be energized when the direction lever is in neutral. The relay should be energized if the parking brake is released with the direction lever in forward or reverse.
Repair: Check for proper operation of the relay. Check for continuity from the parking brake switch to the relay. Check for continuity from the relay to the direction switch.