W DOC AIRBUS | TSM A320F

Speed Sensor P26 Fault (131-9(A))

TASK 49-70-00-810-816-A
Speed Sensor P26 Fault (131-9(A))

1. Possible Causes
  • SPEED SENSOR 1 SHOWS OPEN CIRCUIT
  • SPEED SENSOR 2 SHOWS OPEN CIRCUIT
  • SPEED SENSOR 1 SHOWS AMPLITUDE FAILURE
  • SPEED SENSOR 2 SHOWS AMPLITUDE FAILURE
  • damage/contamination of the electrical connector P26
  • SPEED SENSOR 1 and/or 2
  • aircraft wiring
  • ELECTRONIC CONTROL BOX [59KD]
  • SPEED SENSOR (8060KM)
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
MULTIMETER - STANDARD
 B. Referenced Information
REFERENCE
DESIGNATION
AMM 49-00-00-860-008
APU Start by External Power
ASM 496101
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))
AMM 49-71-13-000-003
Removal of the Speed Sensors (131-9(A))
AMM 49-71-13-400-003
Installation of the Speed Sensors (131-9(A))
3. Fault Confirmation
Subtask 49-70-00-710-084-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 '>'-key adjacent to the related CFDS failure message.
   (4) If the MCDU menu shows:
SPEED SENSOR 1 SHOWS OPEN CIRCUIT

SPEED SENSOR 2 SHOWS OPEN CIRCUIT

  • do the Fault Confirmation that follows:
     (a) Get access to the APU GND SCANNING menu.
   (5) If the MCDU menu shows
SPEED SENSOR 1 SHOWS AMPLITUDE FAILURE

SPEED SENSOR 2 SHOWS AMPLITUDE FAILURE

  • do the Fault Confirmation that follows:
     (a) Start the APU and apply Electrical Load and Bleed Air AMM 49-00-00-860-008.
     (b) Get access to the APU GND SCANNING menu.
4. Fault Isolation
Subtask 49-70-00-810-069-A ** ON A/C NOT FOR ALL
A. If the APU GND SCANNING menu gives the maintenance message:

SPEED SENSOR P26

associated with Fault Code Number (FCN) 7 or 8

  • do a check for damage/contamination of the electrical connector P26 of the SPEED SENSORS 1 / 2.
   (1) If the electrical connector of the SPEED SENSORS 1 and/or 2 is damaged/contaminated:
  • do a repair/cleaning.
   (2) If the electrical connector are OK:
  • use a MULTIMETER - STANDARD to do a resistance check of the electrical connector across
    pin 1 and pin 2 for the SPEED SENSOR 1
    and
    pin 3 and pin 4 for the SPEED SENSOR 2.
     (a) If the resistance is > 25 Ohms:
     (b) If the resistance is OK:
  • do a check and repair of the aircraft wiring from
    the ECB (59KD) AB/E6,E7 to the electrical connector P26/1,2 (SPEED SENSOR 1)
    and
    the ECB (59KD) AB/D3,D4 to the electrical connector P26/3,4 (SPEED SENSOR 2)
    ASM 496101.
       1 If the fault continues:
Subtask 49-70-00-810-070-A ** ON A/C NOT FOR ALL
B. If the APU GND SCANNING menu gives the maintenance message:

SPEED SENSOR P26

associated with Fault Code Number (FCN) 9 or 10

  • do a check for damage/contamination of the electrical connector P26 of the SPEED SENSORS 1 / 2.
   (1) If the electrical connector of the SPEED SENSORS 1 and/or 2 is damaged/contaminated:
  • do a repair/cleaning.
   (2) If the electrical connector are OK:
  • use a MULTIMETER - STANDARD to do a resistance check of the electrical connector P26 across
    pin 1/pin 2 and pin 5 for the SPEED SENSOR 1
    and
    pin 3/pin 4 and pin 5 for the SPEED SENSOR 2.
     (a) If the resistance is < 100 kOhms:
     (b) If the resistance is OK:
  • do a check and repair of the aircraft wiring from
    the ECB (59KD) AB/E6,E7 to the electrical connector P26/1,2 (SPEED SENSOR 1)
    and
    the ECB (59KD) AB/D3,D4 to the electrical connector P26/3,4 (SPEED SENSOR 2)
    ASM 496101.
       1 If the fault continues:
Subtask 49-70-00-810-069-B ** ON A/C NOT FOR ALL
C. If the APU GND SCANNING menu gives the maintenance message:

SPEED SENSOR (8060KM)

associated with Fault Code Number (FCN) 7 or 8

  • do a check for damage/contamination of the electrical connector P26 of the SPEED SENSOR (8060KM)
   (1) If the electrical connector of the SPEED SENSORS 1 and/or 2 is damaged/contaminated:
  • do a repair/cleaning.
   (2) If the electrical connector are OK:
  • use a MULTIMETER - STANDARD to do a resistance check of the electrical connector across
    pin 1 and pin 2 for the SPEED SENSOR 1
    and
    pin 3 and pin 4 for the SPEED SENSOR 2.
     (a) If the resistance is > 25 Ohms:
     (b) If the resistance is OK:
  • do a check and repair of the aircraft wiring from
    the ECB (59KD) AB/E6,E7 to the electrical connector P26/1,2 (SPEED SENSOR 1)
    and
    the ECB (59KD) AB/D3,D4 to the electrical connector P26/3,4 (SPEED SENSOR 2)
    ASM 496101.
       1 If the fault continues:
Subtask 49-70-00-810-070-B ** ON A/C NOT FOR ALL
D. If the APU GND SCANNING menu gives the maintenance message:

SPEED SENSOR (8060KM)

associated with Fault Code Number (FCN) 9 or 10

  • do a check for damage/contamination of the electrical connector P26 of the SPEED SENSOR (8060KM)
   (1) If the electrical connector of the SPEED SENSOR (8060KM) is damaged/contaminated:
  • do a repair/cleaning.
   (2) If the electrical connector are OK:
  • use a MULTIMETER - STANDARD to do a resistance check of the electrical connector P26 across
    pin 1/pin 2 and pin 5 for the SPEED SENSOR 1
    and
    pin 3/pin 4 and pin 5 for the SPEED SENSOR 2.
     (a) If the resistance is < 100 kOhms:
     (b) If the resistance is OK:
  • do a check and repair of the aircraft wiring from
    the ECB (59KD) AB/E6,E7 to the electrical connector P26/1,2 (SPEED SENSOR 1)
    and
    the ECB (59KD) AB/D3,D4 to the electrical connector P26/3,4 (SPEED SENSOR 2)
    ASM 496101.
       1 If the fault continues:
Subtask 49-70-00-710-085-A ** ON A/C NOT FOR ALL
E. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:34:41 UTC
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