Gasboy SERIES 9800Q, Diagnostic Manual

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Troubleshooting
01/28/04 4-11
Quantity shows on 9800Q displays but fuel management system records incorrect or zero
quantity. This problem pertains only to 9800Q’s connected to non-CFN fuel management
systems.
Possible Cause
Checks Corrective Action
Pulser output rate switches
don’t match system pulser
rate. Check the settings of SW2-1
through SW1-4 on the CPU
PCB. Change the CPU PCB switch
settings or change the fuel
management system pulser
rate accordingly.
NOTE: Changing the pulser
rate switches may require
replacement of your Weights
and Measures seal.
Fuel management system
pulser input circuitry not
compatible. The 9800Q requires the fuel
management system to "pull
up" the pulser signal to a DC
voltage between 5VDC and
24VDC. Call GASBOY Technical
Service for assistance.
Defective CPU PCB. Using an oscilloscope, check
the signal between GND (TP2)
and the following pins of P2 on
the pump I/F PCB.:
Pin 5-Side 1 1000:1;
250:1, international
Pin 6-Side 2 1000:1;
250:1, international
Pin 10-Side 1 below 1000:1;
below 250:1 international
Pin 11-Side 2 below 1000:1;
below 250:1 international Replace the CPU PCB if a
+5VDC square wave signal is
not measured on the
appropriate pins.
NOTE: Replacing the CPU
PCB may require replacement
of your Weights and Measures
seal.
Defective Pump I/F PCB. Using an oscilloscope, check
the signal between GND (TP2)
and P1 pin 1 (side 1) or P1 pin
2 (side 2) on the pump I/F
PCB. Replace the Pump I/F PCB if
the pulser signal is not
measured on the appropriate
pins.
Replace the power supply if
0VDC is measured on both
sides of F1 or F2.