APU AUTO SHUT DOWN - BACKUP OVERSPEED, ECB 59KD or Cooling Fan/PMG Assy(8055KM) or Fuel Control-Unit or Fault or Speed Sensors Failures, (APS 3200)

TASK 49-00-00-810-932-A
APU AUTO SHUT DOWN - BACKUP OVERSPEED, ECB 59KD or Cooling Fan/PMG Assy(8055KM) or Fuel Control-Unit or Fault or Speed Sensors Failures, (APS 3200)

1. Possible Causes

PMG COOLING FAN connector P28
wiring
ELECTRONIC CONTROL BOX [59KD]
PMG COOLING FAN ASSEMBLY (8055KM)
FUEL CONTROL UNIT (8022KM)
SPEED SENSOR 1 (8060KM1)
SPEED SENSOR 2 (8060KM2)

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 49-00-00-810-893-A	APU AUTO SHUT DOWN - OVERSPEED, Fuel Control Unit or ECB Fault (APS 3200)
ESPM 204821A
ESPM 2052210
ESPM 2052240
ESPM 2053210
ESPM 205321A
AMM 49-00-00-710-008	Operational Test of the APU
AMM 49-52-53-000-001	Removal of the PMG and Cooling Fan Assembly (APS 3200)
AMM 49-52-53-400-001	Installation of the PMG and Cooling Fan Assembly (APS 3200)
ASM 496102
AMM 49-61-34-000-002	Removal of the Electronic Control Box (ECB) (APS 3200)
AMM 49-61-34-400-002	Installation of the Electronic Control Box (ECB) (APS 3200)
AMM 49-71-13-000-002	Removal of the Speed Sensor (APS 3200)
AMM 49-71-13-400-002	Installation of the Speed Sensor (APS 3200)

3. Fault Confirmation
Subtask 49-00-00-710-300-A ** ON A/C NOT FOR ALL

A. Do the operational test of the APU AMM 49-00-00-710-008.

NOTE: If the APU SHUTDOWNS report gives the message OVERSPEED - FUEL CTL UNIT P19 OR ECB 59KD do the applicable trouble shooting procedure (Ref. TSM TASK 49-00-00-810-893).

4. Fault Isolation
Subtask 49-00-00-810-239-C ** ON A/C NOT FOR ALL

A. If the APU Last Leg Report gives the maintenance message:

COOLING FAN PMG ASSY (8055KM)
Fault Code Number: 115

NOTE: The APU SHUTDOWNS report gives the maintenance message:
BACKUP OVERSPEED - COOLING FAN PMG ASSY (8055KM)
APU Auto Shut Down Fault Code Number: 115.

NOTE: If the APU Last Leg Report gives the maintenance message: COOLING FAN PMG ASSY (8055KM) Fault Code Number (FCN) 115 and the APU SHUTDOWN report shows that the fault occurred during engine spool down between 15% and 0% speed, you can ignore this fault because it is not important.

do a check of the PMG COOLING FAN connector P28 and replace the contacts in bad condition ESPM 2052240 ESPM 204821A.

do a check and repair the wiring from the ELECTRONIC CONTROL BOX [59KD] AC/10, 11 to the PMG COOLING FAN ASSEMBLY (8055KM) P28/2, 3 and from the ELECTRONIC CONTROL BOX [59KD] AB/4H to the PMG COOLING FAN ASSEMBLY (8055KM) P28/1 ASM 496102 ESPM 2052210 ESPM 2053210 ESPM 205321A.

(1) If the fault continues:

replace the PMG COOLING FAN ASSEMBLY (8055KM) AMM 49-52-53-000-001 and AMM 49-52-53-400-001.

(a) If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-002 and AMM 49-61-34-400-002.

Subtask 49-00-00-810-368-G ** ON A/C NOT FOR ALL

B. If the APU Last Leg Report gives the maintenance message:

FUEL CTL UNIT (8022KM)

Fault Code Number: 115
Additionally:
Fault Code Number: 068

NOTE: The APU SHUTDOWNS report gives the maintenance message: BACKUP OVERSPEED - FUEL CTL UNIT (8022KM) - APU Auto Shut Down Fault Code Number: 115.

replace the FUEL CONTROL UNIT (8022KM) AMM 49-52-53-000-001 and AMM 49-52-53-400-001.

(1) If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-002 and AMM 49-61-34-400-002.

(a) If the fault continues:

do a check and repair the wiring from the ELECTRONIC CONTROL BOX [59KD] AB/10H, 11H to the FUEL CONTROL UNIT (8022KM) P19/3, 4 ASM 496102 ESPM 2052210 ESPM 2053210 ESPM 205321A.

Subtask 49-00-00-810-369-A ** ON A/C NOT FOR ALL

C. If the APU Last Leg Report gives the maintenance message:

ECB (59KD):
Fault Code Number: 115
Additionally:
Fault Code Number: 061

NOTE: The APU SHUTDOWNS report gives the maintenance message:
BACKUP OVERSPEED - ECB (59KD)
APU Auto Shut Down Fault Code Number: 115

NOTE: The APU SHUTDOWNS report gives the maintenance message: ECB FAILURE - ECB (59KD) One out of APU Auto Shut Down Fault Code Number: 061.

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-002 and AMM 49-61-34-400-002.

Subtask 49-00-00-810-370-G ** ON A/C NOT FOR ALL

D. If the APU Last Leg Report gives the maintenance message:

SPD SNSR1 (8061KM1) and SPD SNSR2 (8060KM2)

Fault Code Number: 115
Additionally:
Fault Code Number: 034

NOTE: The APU SHUTDOWNS report gives the maintenance message: BACKUP OVERSPEED - FUEL CTL UNIT (8022KM) - APU Auto Shut Down Fault Code Number: 115.

NOTE: FCN 034 on Class 3 Faults Page.

replace the SPEED SENSOR 1 (8060KM1) and the SPEED SENSOR 2 (8060KM2) AMM 49-71-13-000-002 and AMM 49-71-13-400-002.

(1) If the fault continues:

do a check and repair the wiring from the ELECTRONIC CONTROL BOX [59KD] AB/A10, A11 to the SPEED SENSOR 1 (8060KM1) P26/1, 2 ASM 496102 ESPM 2052210 ESPM 2053210 ESPM 205321A.

(a) If the fault continues:

do a check and repair the wiring from the ELECTRONIC CONTROL BOX [59KD] AB/B5, B6 to the SPEED SENSOR 2 (8060KM2) P27/1, 2 ASM 496102 ESPM 2052210 ESPM 2053210 ESPM 205321A.

1 If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-002 and AMM 49-61-34-400-002.

Subtask 49-00-00-710-301-B ** ON A/C NOT FOR ALL

E. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:34:26 UTC