Smiths Aerospace
Electronic Systems – Malvern
DOC NO.0134ED
MAINTENANCE MANUAL SUPPLEMENT
BOEING B737-100/200/300/400/500
28-41-04
OK
Do this procedure: “Prepare for Troubleshooting”. Do this task: “Operational Test – Fuel Quantity
Indicating System” (AMM 28-41-04/501). Do a check to see if the indicators operate. IF -
ALL FUEL QUANTITY INDICATORS DO NOT OPERATE
CORRECTLY – Replace the refueling power select relay, R10, in
the E3 electrical shelf.
NOT OK
Push the FUEL QTY TEST switch and hold it. The value on the indicator must go to zero. Then the
indicator must show ERR after 5-10 seconds. Release the test switch. The indicator shows the error
codes kept in its memory, if there are error codes in its memory (2 seconds for each error code), then all
segments come on for approximately 2 seconds. Then the display shows the full tank quantity for
approximately 2 seconds. Then the display shows its initial value with a tolerance of +/- 20 pounds (+/- 20
kilograms).
IF -
OK
THE INDICATOR DOES NOT DO THE SELF-TEST – Replace the fuel QTY
TEST switch, S257.
THE FUEL QUANTITY INDICATOR SHOWS ERROR CODE 1 DURING THE
SELF-TEST – FIG. 102
THE FUEL QUANTITY INDICATOR SHOWS ERROR CODE 2 DURING THE
SELF-TEST – FIG. 103
THE FUEL QUANTITY INDICATOR SHOWS ERROR CODE 3 DURING THE
SELF-TEST – FIG. 104
THE FUEL QUANTITY INDICATOR SHOWS ERROR CODE 4
DURING THE SELF-TEST – FIG. 105
THE FUEL QUANTITY INDICATOR SHOWS ERROR CODE 5
DURING THE SELF-TEST – FIG. 106
THE FUEL QUANTITY INDICATOR SHOWS ERROR CODE 6
DURING THE SELF-TEST – FIG. 107
NOT OK
NOT OK
NOT OK
NOT OK
NOT OK
NOT OK
NOT OK
Troubleshooting for the Fuel Quantity Indicating System
Figure 101 (Sheet 1)
Page 105
July 15/02
Airplanes with Smiths 2307 Model Fuel Quantity
Indicators with TSU
EFFECTIVITY
