Fuel filter bypass light (B737-800)
Thread Starter
Join Date: May 2011
Location: Seoul, South Korea
Age: 43
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Fuel filter bypass light (B737-800)
Hi there,
Q:
I want to know why FUEL FILTER BYPASS LT do not illuminate when
CDU INPUT MONITORING/FUEL FILTER screen shows the filter is "CLOGGED" even though the affected engine START switch is in CONT position per DDG 73-04-02(M).
Is it normal or not? Please give me some advice
The faulty differential switch caused the problem. The defect was cleared with new differential switch replaced per FIM task, but I don't have a idea why the DDG procedure followed by me could not cause the FUEL FILTER BYPASS light to illuminate. I am not sure, but I belive that the light should be ON when the affected engine start switch is in CONT position becuase the switch is included in fuel filter bypass warning system. Please refer to the followings.
DDG 73-04-02(M) :
Verify that the malfunction is in the fuel filter bypass warning system
1. If the FILTER BYPASS light illuminates with the engine no operating, the fuel filter bypass warning system is faulty.
NOTE : To energize the system with the engine not operating, position the engine START switch to CONT.
Q:
I want to know why FUEL FILTER BYPASS LT do not illuminate when
CDU INPUT MONITORING/FUEL FILTER screen shows the filter is "CLOGGED" even though the affected engine START switch is in CONT position per DDG 73-04-02(M).
Is it normal or not? Please give me some advice
The faulty differential switch caused the problem. The defect was cleared with new differential switch replaced per FIM task, but I don't have a idea why the DDG procedure followed by me could not cause the FUEL FILTER BYPASS light to illuminate. I am not sure, but I belive that the light should be ON when the affected engine start switch is in CONT position becuase the switch is included in fuel filter bypass warning system. Please refer to the followings.
DDG 73-04-02(M) :
Verify that the malfunction is in the fuel filter bypass warning system
1. If the FILTER BYPASS light illuminates with the engine no operating, the fuel filter bypass warning system is faulty.
NOTE : To energize the system with the engine not operating, position the engine START switch to CONT.
