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| Illustration 1 | g00498361 |
(1) Rod (2) Dump body position sensor | |
The dump body position sensor (2) is located on the left rear frame near the pivot pin for the dump body. The rod (1) is connected between the dump body position sensor (2) and the dump body. When the dump body is raised, the rod (1) rotates the dump body position sensor (2), which changes the Pulse Width Modulated signal that is sent to the Power Train Electronic Control Module (Power Train ECM). The adjustment of the rod between the sensor and the dump body is very important. The length of the rod should be 360.0 ± 3.0 mm (14.17 ± 0.12 inch) from the center of both rod ends.
After rod (1) has been adjusted, the Power Train ECM will perform a calibration. The dump body position sensor (2) is calibrated by the Power Train ECM when all of the following conditions exist:
- The engine is running for one minute with no ground speed.
- The hoist control is in the FLOAT position.
- The signal from the dump body position sensor is 6 degrees different from the previous calibration.
- The duty cycle output must be less than 20 percent.
The dump body position sensor (2) is used to limit the top gear while the dump body is up. The Power Train ECM comes from the factory with the top gear value that is set to FIRST gear. The transmission will not shift past FIRST gear until the dump body is down. The top gear value is programmable by utilizing the Electronic Control Analyzer Programmer (ECAP) or the Electronic Technician (ET). The top gear value can be changed to SECOND gear, THIRD gear, or FOURTH gear.
The signal from dump body position sensor (2) is also used to control the SNUB position of the hoist control valve. The Power Train ECM will signal the hoist proportioning solenids to move the hoist control valve to the SNUB position when the dump body that is being lowered nears the frame. The speed in FLOAT is reduced in the SNUB position in order to prevent the dump body from contacting the frame too hard.
The signal from the dump body position sensor (2) is used to provide warnings to the operator when the truck is moving with the dump body UP.