Smiths Aerospace
Electronic Systems – Malvern
DOC NO.0134ED
MAINTENANCE MANUAL SUPPLEMENT
BOEING B737-100/200/300/400/500
28-41-04
4. System Calibration
Perform the following steps as required.
A. Preparation for the system test.
1. Provide electrical power (Ref. AMM Chapter 24).
2. Extend leading edge flaps (Ref. AMM Chapter 27).
WARNING: YOU MUST CAREFULLY DO THE STEPS BELOW TO INSTALL THE LE FLAP SAFETY LOCKS.
THE LE FLAPS CAN MOVE QUICKLY IF YOU DO NOT INSTALL THE SAFETY LOCKS
CORRECTLY. THIS CAN CAUSE INJURY TO PERSONS OR DAMAGE TO THE EQUIPMENT.
3. Install safety locks on the leading edge flaps (Ref. AMM Chapter 27).
4. Defuel/drain all tanks to be calibrated and associated sumps so that the compensators and tank units
will not be immersed in fuel (Ref. AMM Chapter 28).
5. If aircraft is equipped with capacitance trimmers for the FQIS system (located above the hand mike jack
on the pilot’s side of the center console), they should be adjusted to minimum capacitance as follows:
Remove the trimmer’s plastic cover by unthreading it to reveal the adjustment screw. Back the trimmer
screw CCW until flush with internally threaded tube, turn clockwise one or two turns until resistance to
rotation is felt. Reinstall the trimmer’s plastic cover.
B. Adjust fuel quantity indicator (empty) at the pilot’s panel.
1. Open “FUEL QTY” circuit breaker.
2. At the pilot’s panel, pull the indicator of tank to be calibrated out from the panel for access to the
DCTU. Remove the screw and slide the ID plate off the back of the DCTU with the indicator remaining
connected.
3. Place “CAL-RUN” jumper in “CAL” mode.
4. Close “FUEL QTY” circuit breaker. The indicator will display “CAL”.
5. Depress both “UP” and “DOWN” select buttons simultaneously. The indicator will display “P01” for one
second and one analog segment will illuminate. After displaying “P01”, the display will change to show
either “LB” or “KG”.
6. Adjust to the appropriate units by pressing the “UP” button for LB and the “DOWN” button for the KG
units.
7. Depress both “UP” and “DOWN” select buttons simultaneously. The indicator will display “P02” for one
second and two analog segments will illuminate. After displaying “P02”, the display will change to show
the last entered value.
CONFIG
4.1
Page 519
July 15/02
Airplanes with Smiths 2307 Model Fuel Quantity Indicators
with TSU
(GULL SYSTEM TESTER)
EFFECTIVITY
