Floscan TwinScan GPH/LPH Meter - Manual (Page 19)

8/30/2004 1000-204-00C
FloScan Instrument Company, Inc. Tel: (206) 524-6625 Fax: (206) 523-4961
3016 NE Blakeley Street, Seattle, WA 98105 Email: [email protected] Http://www.floscan.com
FAULT PROBABLE CAUSE SEE SECTION:
Blank LCD Display Wiring Section III
No back-lighting Wiring/bulb failure Section
Low Totalizer Reading, over 10% Calibration Calibration sheet
Sensor orientation/failure Section IV, Install. sheets
High Totalizer Reading, over 10% Incorrect/defective sensor Section IV
Incorrect switch settings Calibration sheet
Suction leak Section VII
Fluctuating GPH Readings Suction leak Section VII
Low RPM operation Section X
No GPH or Totalizer Reading Wiring/Instrument failure Section I, II, III, and V
Sensor orientation/failure Section IV, Install. sheet
Wire Harness Continuity Test Section V
III. SUPPLY VOLTAGE and GROUND TEST
• Measure voltage between the Starboard RED power wire, and the BLACK Instrument ground wire.
__________VDC
• Measure voltage between the Port RED/WHITE power wire, and the BLACK Instrument ground wire.
__________VDC
These readings should be approximately 12 - 14 VDC, but not lower than 10 VDC.
• If 12 VDC is not present, measure between the RED, or RED/WHITE power wire and a known good ground
in the instrument panel. If you measure 12 to 14 VDC, there may be an instrument ground problem. __________VDC
• If 12 to 14 VDC is not present check wiring, switches, fuse, and the 12 VDC power source.
IV. SENSOR(S) TEST
1. With your voltmeter set to a DC scale greater than 14 volts, measure between the RED (+12VDC) and
BLACK (Instrument ground) wires. With engine idling, measure and record the voltage reading. ___________VDC
2. Move the voltmeters’ negative lead to the WHITE (Signal) wire. With engine idling, measure and record
the voltage reading. Readings between 4 and 10 VDC usually indicate a good sensor. ___________VDC
3. Stop the engine while observing the voltmeter. Readings should fluctuate between a high of 9 to 12 VDC,
and a low of 0 to 4 VDC as the sensors’ turbine slows to a stop. ___________VDC
NOTE: This may not be seen on a digital voltmeter.
4. Move the voltmeters’ negative lead to the BROWN (Signal) wire. With engine idling, measure and record
the voltage reading. Readings between 4 and 10 VDC usually indicate a good sensor. ___________VDC
5. Stop the engine and observe the voltmeter. Voltage readings should fluctuate between a high of 9 to 12
VDC, and a low of 0 to 4 VDC as the Sensors’ turbine slows to a stop.
NOTE: This may not be seen with a digital voltmeter.
6. The Sensor may be defective if voltage readings in steps 3 & 5 remain constant while the engine is
stopping.
7. On twin engine systems, try swapping the Brown & White signal wires. Observe the Instrument and see if the
problem shifts sides, or remains on the same side.