APU AUTO SHUT DOWN - NO ACCELERATION, Main Start-Contactor Fault (APS 3200)

TASK 49-00-00-810-878-A
APU AUTO SHUT DOWN - NO ACCELERATION, Main Start-Contactor Fault (APS 3200)

1. Possible Causes

CONTACTOR-MAIN START [5KA]
wiring
MOTOR-STARTER [8KA]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
ESPM 2052210
ESPM 2053210
AMM 49-00-00-710-008	Operational Test of the APU
ASM 494201
AMM 49-42-51-000-007	Removal of the Starter Motor (APS 3200)
AMM 49-42-51-400-007	Installation of the Starter Motor (APS 3200)
AMM 49-42-55-000-001	Removal of the Start Contactors
AMM 49-42-55-400-001	Installation of the Start Contactors

3. Fault Confirmation
Subtask 49-00-00-710-204-A ** ON A/C NOT FOR ALL

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

4. Fault Isolation
Subtask 49-00-00-810-129-B ** ON A/C NOT FOR ALL

A. Maintenance Action
(1) If the APU Last Leg Report gives the maintenance message:

CONTACTOR (5KA):
Fault Code Number: 051
Additionally:
Fault Code Number: 128

NOTE: The APU SHUTDOWNS report gives the maintenance message:
NO ACCELERATION - CONTACTOR (5KA)
APU Auto Shut Down Fault Code Number: 051

replace the CONTACTOR-MAIN START [5KA] AMM 49-42-55-000-001 and AMM 49-42-55-400-001.

(a) If the fault continues:

do a check and repair the wiring from the Contactor Back-up Start (10KA) A/F to the Contactor Main Start (5KA) A/D ASM 494201 ESPM 2052210 ESPM 2053210.

(b) If the fault continues:

do a check and repair the wiring from the Contactor Main Start (5KA) A/F to the Starter Motor (8KA) ASM 494201 ESPM 2052210 ESPM 2053210.

do a check and repair the wiring from the ECB (59KD) AB/J10 to the positive electrical connection of the Starter Motor (8KA) ESPM 2052210 ESPM 2053210 ASM 494201.

(d) If the fault continues:

replace the MOTOR-STARTER [8KA] AMM 49-42-51-000-007 and AMM 49-42-51-400-007.

(2) If the APU Last Leg Report gives the maintenance message:

CONTACTOR (5KA):
Fault Code Number: 051
Additionally:
Fault Code Number: 017

NOTE: The APU SHUTDOWNS report gives the maintenance message:
NO ACCELERATION - CONTACTOR (5KA)
APU Auto Shut Down Fault Code Number: 051

do a check and repair the wiring from the ECB (59KD) AC/1 to the Contactor Main Start (5KA) B/3 ASM 494201 ESPM 2052210 ESPM 2053210.

(a) If the fault continues:

replace the CONTACTOR-MAIN START [5KA] AMM 49-42-55-000-001 and AMM 49-42-55-400-001.

Subtask 49-00-00-710-205-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:34:23 UTC