9. Forcibly clear the data for the total payload and overall number of cycles. With this operation performed, all the unwanted data inside the payload meter is cleared. Except for the calibration data, all the data recorded in the previous steps is also erased. 10. After this procedure has been performed the system is ready for normal function. SUSPENSION PRESSURE SENSOR The pressure sensors are mounted on top of each suspension cylinder. The sensors produce a voltage signal from 1 – 5 volts output. FIGURE 20-11. BATTERY CONNECTION After Replacing the Battery The pressure sensor is mounted to the suspension cylinder using a Schrader Valve assembly, adapter and sensor.
The sensor can be replaced without re- leasing the pressure in the suspension by removing the sensor with the adapter. While replacing the battery, the backup power source for the memory inside the payload meter is momentar- ily disconnected. This can allow unwanted data (garbage) to enter the memory and affect the meter’s recognition proce- dures. The following will remove this unwanted data. Removal 1. Turn the keyswitch to the ON position. may flash. Ensure the adapter and sensor are removed to- gether from the valve assembly. Removing the complete valve assembly or just the sensor may result in the component being forced out of the suspension by the gas pressure inside. 2.
Using the Operator Check Mode, set the speed limit option code, time and date. (These were erased from memory when the battery was dis- connected). 1. Disconnect sensor from truck wiring harness. 3. Without turning the keyswitch to the OFF position advance to the start position. With the engine running, the display: may flash. Note: The Schrader valve in the valve assembly will prevent gas from escaping when adapter and sensor are removed together . If entire valve assembly is turned allowing nitrogen gas to escape, recharging of the suspension will be required . 4. Perform the calibration procedure. Refer to "Calibrating a Truck". 2.
Hold valve (2, Figure 20-11) with wrench while removing the adapter/sensor assembly (3 & 4). 5. Load the truck to the rated payload, or close to it. Dump the load. 3. Remove sensor (4) from adapter (3). 6. Move the truck to a safe area, wait at least 5 seconds after dumping the load, then shut the truck down. 7. Turn the keyswitch back to the ON position but do not start the engine. 8. Perform the Data All Clear in the Operator Check mode. FIGURE 20-10. PRESSURE SENSOR. 1. Schrader Valve 3. Adapter 2. Valve Assembly 4. Sensor M20007.1 03/02 Payload Meter II M20-29