Inlet Pressure Transducer (P22) Fault (131-9(A))

TASK 49-00-81-810-860-A
Inlet Pressure Transducer (P22) Fault (131-9(A))

1. Possible Causes

INLET PRESSURE SENSOR SHOWS OUT OF RANGE
INLET PRESSURE SENSOR SHOWS < 8 PSIA ON GROUND
INLET PRESSURE SENSOR SHOWS OUT OF RANGE LOW
INLET PRESSURE SENSOR SHOWS OUT OF RANGE HIGH
INLET PRESSURE SENSOR SHOWS < 6.5 PSIA ON GROUND
damage/contamination of electrical connector P22
INLET PRESSURE TRANSDUCER (P22)
aircraft wiring
ELECTRONIC CONTROL BOX [59KD]
INLET PRESSURE TRANSDUCER (8048KM)
damage/contamination of electrical connector P23
TOTAL PRESSURE TRANSDUCER (P23)
TOTAL PRESSURE TRANSDUCER (8044KM)
DIFFERENTIAL PRESSURE TRANSDUCER (8048M)

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 49-51-17-000-002	Removal of the Transducer - Total Pressure (131-9(A))
AMM 49-51-17-400-002	Installation of the Transducer - Total Pressure (131-9(A))
AMM 49-51-21-000-001	Removal of the Transducer - APU Inlet Pressure (131-9(A))
AMM 49-51-21-400-001	Installation of the Transducer - APU Inlet Pressure (131-9(A))
ASM 496104
AMM 49-61-34-000-003	Removal of the Electronic Control Box (ECB) (131-9(A))
AMM 49-61-34-400-003	Installation of the Electronic Control Box (ECB) (131-9(A))

3. Fault Confirmation
Subtask 49-00-81-710-070-A ** ON A/C NOT FOR ALL

A. Read-out of ECB Trouble-Shooting Data
(1) Put the APU MASTER SW to the ON position.
(2) Get access to the APU LAST LEG/PREVIOUS LEG report.
(3) Push the '>' adjacent to the related CFDS failure message:

the MCDU menu shows:
INLET PRESSURE SENSOR SHOWS OUT OF RANGE
or
INLET PRESSURE SENSOR SHOWS < 8 PSIA ON GROUND
or
INLET PRESSURE SENSOR SHOWS OUT OF RANGE LOW
or
INLET PRESSURE SENSOR SHOWS OUT OF RANGE HIGH

(4) Get access to the APU GND SCANNING menu.

Subtask 49-00-81-710-070-B ** ON A/C NOT FOR ALL

the MCDU menu shows:
INLET PRESSURE SENSOR SHOWS OUT OF RANGE
or
INLET PRESSURE SENSOR SHOWS < 6.5 PSIA ON GROUND
or
INLET PRESSURE SENSOR SHOWS OUT OF RANGE LOW
or
INLET PRESSURE SENSOR SHOWS OUT OF RANGE HIGH

(4) Get access to the APU GND SCANNING menu.

4. Fault Isolation
Subtask 49-00-81-810-063-A ** ON A/C NOT FOR ALL

A. If the APU GND SCANNING menu gives the maintenance message:

INLET PRESS XDCR P22

associated with Fault Code Number (FCN) 21, 22, 23 or 24

do a check for damage/contamination of electrical connector P22 of the INLET PRESSURE TRANSDUCER (P22)

(1) If the electrical connector P22 is damaged/contaminated:

do a repair/cleaning.

(2) If the electrical connector is OK:

replace the INLET PRESSURE TRANSDUCER (P22) AMM 49-51-21-000-001 and AMM 49-51-21-400-001.

(a) If the fault continues:

do a check and repair of the aircraft wiring from the ECB (59KD) AB/C8,C9 to the INLET PRESSURE TRANSDUCER (P22) P22/3,4 ASM 496104.

1 If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-003 and AMM 49-61-34-400-003.

Subtask 49-00-81-810-167-A ** ON A/C NOT FOR ALL

B. If the TEST menu or the APU GND SCANNING menu gives the maintenance message:

TOTAL PRESS XDCR P23

associated with Fault Code Number (FCN) 27

do a check for damage/contamination of electrical connector P23 of the TOTAL PRESSURE TRANSDUCER (P23)
do a check for damage/contamination of electrical connector P22 of the INLET PRESSURE TRANSDUCER (P22)

(1) If the electrical connector P23/P22 are damaged/contaminated:

do a repair/cleaning.

(2) If the electrical connectors are OK:

replace the TOTAL PRESSURE TRANSDUCER (P23) AMM 49-51-17-000-002 and AMM 49-51-17-400-002.

(a) If the fault continues:

replace the INLET PRESSURE TRANSDUCER (P22) AMM 49-51-21-000-001 and AMM 49-51-21-400-001.

1 If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-003 and AMM 49-61-34-400-003.

Subtask 49-00-81-810-063-B ** ON A/C NOT FOR ALL

C. If the APU GND SCANNING menu gives the maintenance message:

INLET PRESS XDCR (8048KM)

associated with Fault Code Number (FCN) 21, 22, 23 or 24

do a check for damage/contamination of electrical connector P22 of the INLET PRESSURE TRANSDUCER (8048KM)

(1) If the electrical connector P22 is damaged/contaminated:

do a repair/cleaning.

(2) If the electrical connector is OK:

replace the INLET PRESSURE TRANSDUCER (8048KM) AMM 49-51-21-000-001 and AMM 49-51-21-400-001.

(a) If the fault continues:

do a check and repair of the aircraft wiring from the ECB (59KD) AB/C8,C9 to the INLET PRESSURE TRANSDUCER (8048KM) P22/3,4 ASM 496104.

1 If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-003 and AMM 49-61-34-400-003.

Subtask 49-00-81-810-167-B ** ON A/C NOT FOR ALL

D. If the TEST menu or the APU GND SCANNING menu gives the maintenance message:

TOTAL PRESS XDCR (8044KM)

associated with Fault Code Number (FCN) 27

do a check for damage/contamination of electrical connector P23 of the TOTAL PRESSURE TRANSDUCER (8044KM).
do a check for damage/contamination of electrical connector P22 of the INLET PRESSURE TRANSDUCER (8048M)

(1) If the electriacl connectors P23/P22 are damaged/contaminated:

do a repair/cleaning.

(2) If the electrical connectors are OK:

replace the TOTAL PRESSURE TRANSDUCER (8044KM) AMM 49-51-17-000-002 and AMM 49-51-17-400-002.

(a) If the fault continues:

replace the DIFFERENTIAL PRESSURE TRANSDUCER (8048M) AMM 49-51-21-000-001 and AMM 49-51-21-400-001.

1 If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-003 and AMM 49-61-34-400-003.

Subtask 49-00-81-710-071-A ** ON A/C NOT FOR ALL

E. Do a check of the APU GND SCANNING menu to verify the fault is not present.

[Rev.8 from Aug 2018] 2026.04.04 04:34:36 UTC