CARTRIDGE ASSEM. 3S8444 - Caterpillar

Illustration 1 g02243854
Front view of a typical payload monitor indicating the Processor LED (1) and the Data LED (2).
Table 1
Troubleshooting Chart
Symptom Possible Cause Cure
No numbers on payload display. No power to payload display. Turn power OFF and back ON. The payload display should show revision number, or check to see if Processor LED (1) is ON .
No Processor LED (1). No power to payload display or payload display is dead. Remove the rear connector and check supply voltage coming to the Display. If there is power on the Display, then set the option switches to show all 8's (Option 1). If there is power but no 8's, then the Display is dead and should be returned to the factory.
Processor LED (1) blinks but no data displays. No data being received or the receive circuit in payload display is dead. Check Data Receive LED (2). The LED should blink on each time the TPMS or VIMS unit transmits to the payload display.
Processor LED (1) blinks but no data displays. Wrong data or the receive circuit in payload display is dead. Check to see if the option switches are set to match the TPMS or VIMS truck the payload display is attached to. Otherwise, if the correct data is received, the payload display input circuit may be dead.
Data Receive LED (2) never blinks. No connection from TPMS or VIMS to payload display. Check connections to the TPMS or VIMS unit.
Numbers are displayed but are off by 10-20%. Wrong conversion for payload display. Check to see if the METRIC/ENGLISH option switch is in the proper position.
Payload display shows 888 all the time. Option switches set to test position. Turn OFF option switches 1 and 2.
First payload display works but second payload display does not work. The output from the first payload display is dead or the input to the second payload display is dead. The first payload display output or the second payload display input is not working. First, check the Data Receive LED on the second payload display. Swap the two payload displays to determine the problem.
The system works but the payload display is off by two or three digits. The TPMS or VIMS unit is sending different data to the payload display. The payload display is a dumb Display. The display only displays the information sent by the TPMS or VIMS unit. The payload display does not calculate or measure the weight. The TPMS or VIMS unit may send data to the payload display that varies slightly from the internal cab display.
The system works until connected to a telemetry system, then one or both units stop working. The RS232 port is loaded by having two devices connected to the output of the TPMS or VIMS unit. Check the setting for use with a telemetry system.