Smiths Aerospace
Electronic Systems – Malvern
DOC NO.0134ED
MAINTENANCE MANUAL SUPPLEMENT
BOEING B737-100/200/300/400/500
28-41-04
Remove Master
Indicator and replace
with new unit. Confirm
fluctuations persist
(AMM 28-41-04/401)
Clear FQI errors and
confirm excessive
fluctuations persist
Check TSU ground stud to
airframe.
Repair
(AMM 28-41-04/401)
> 8 miliohms
> 8 miliohms
Repair
(AMM 28-41-04/401)
Replace Master Indicator
Cleared
Persist
Remove Master Indicator and
DCTU. Measure Hi-Z shield to
ground resistance.
Check TSU bond to
airframe.
< 1 ohm
> 1 ohm
Repair Hi-Z shield
(WDM 28-41-01)
< 8 miliohms
< 8 miliohms
Replace TSU
(AMM 28-41-04/401)
Operational Test
(AMM 28-41-04/501)
Excessive Fluctuations
Figure 109
Page 123
April 19/02
Airplanes with Smiths 2307 Model Fuel Quantity
Indicators with TSU
EFFECTIVITY