Loss of the feedback Signal from the VSV through the Channel A on Engine 2
TASK 75-32-00-810-806-A
Loss of the feedback Signal from the VSV through the Channel A on Engine 2
1. Possible Causes
A. Referenced Information
3. Fault Confirmation
Subtask 75-32-00-710-060-A ** ON A/C NOT FOR ALL
Subtask 75-32-00-810-055-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:37:11 UTC
Loss of the feedback Signal from the VSV through the Channel A on Engine 2
1. Possible Causes
- harness J11
- ECU [4000KS]
- harness CJ11R
- VSV actuator
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| AMM 73-21-50-000-002 | Removal of the CJ11R Harness |
| AMM 73-21-50-000-010 | Removal of the J11 Harness |
| AMM 73-21-50-000-026 | Removal of the CJ11R Harness for SAC Engines |
| AMM 73-21-50-000-044 | Removal of the HJ11 Harness for SAC Engines |
| AMM 73-21-50-400-002 | Installation of the CJ11R Harness |
| AMM 73-21-50-400-010 | Installation of the J11 Harness |
| AMM 73-21-50-400-026 | Installation of the CJ11R Harness for SAC Engines |
| AMM 73-21-50-400-044 | Installation of the HJ11 Harness for SAC Engines |
| AMM 73-21-60-000-001 | Removal of the Electronic Control Unit (ECU) |
| AMM 73-21-60-400-001 | Installation of the Electronic Control Unit (ECU) |
| ASM 732518 | |
| AMM 73-29-00-710-040 | Operational Test of the FADEC on the ground (with Engine Motoring) |
| AMM 75-32-10-000-001 | Removal of the Variable Stator Vane (VSV) Actuators |
| AMM 75-32-10-000-002 | Removal of the Variable Stator Vane (VSV) Actuators |
| AMM 75-32-10-400-001 | Installation of the Variable Stator Vane (VSV) Actuators |
| AMM 75-32-10-400-002 | Installation of the Variable Stator Vane (VSV) Actuators |
Subtask 75-32-00-710-060-A ** ON A/C NOT FOR ALL
A. Test
(1) Do the operational test of the FADEC 2A on the ground (with engine motoring) AMM 73-29-00-710-040.
4. Fault Isolation(1) Do the operational test of the FADEC 2A on the ground (with engine motoring) AMM 73-29-00-710-040.
Subtask 75-32-00-810-055-A ** ON A/C NOT FOR ALL
A. If the test gives the maintenance message VSV ACT, J11, ECU ENG2A:
Subtask 75-32-00-810-065-A ** ON A/C NOT FOR ALL - do a check for open or short to ground of the harness J11 between the ECU (4000KS) and the 6 o'clock junction box, between the 6 o'clock junction box and the VSV LVDT ASM 732518.
- repair the above wiring.
- disconnect the cable J11 from the ECU (4000KS) and do a resistance check of the cable J11 between:
. pins 12 and 28 (400 to 600 Ohms)
. pins 26 and 27 (100 to 180 Ohms)
. pins 10 and 25 (100 to 180 Ohms)
. pins 12 and 11 (> 10 Megohms)
. pins 26 and 11 (> 10 Megohms)
. pins 10 and 11 (> 10 Megohms)
. pin 12 and the ground (> 10 Megohms)
. pin 26 and the ground (> 10 Megohms)
. pin 10 and the ground (> 10 Megohms).
- replace the ECU [4000KS] AMM 73-21-60-000-001 and AMM 73-21-60-400-001.
- disconnect the cable J11 from the cable CJ11R at the 6 o'clock junction box and do a resistance check of the cable CJ11R between:
. pins 4 and 14 (400 to 600 Ohms)
. pins 1 and 6 (100 to 180 Ohms)
. pins 15 and 27 (100 to 180 Ohms)
. pins 4 and 5 (> 10 Megohms)
. pins 1 and 5 (> 10 Megohms)
. pins 15 and 5 (> 10 Megohms)
. pin 4 and the ground (> 10 Megohms)
. pin 1 and the ground (> 10 Megohms)
. pin 15 and the ground (> 10 Megohms).
- replace the harness J11 AMM 73-21-50-000-010 and AMM 73-21-50-400-010.
- disconnect the cable CJ11R from the VSV actuator and do a resistance check of the VSV actuator between:
. pins 2 and 3 (400 to 600 Ohms)
. pins 4 and 5 (100 to 180 Ohms)
. pins 6 and 7 (100 to 180 Ohms)
. pin 2 and the ground (> 10 Megohms)
. pin 4 and the ground (> 10 Megohms)
. pin 6 and the ground (> 10 Megohms).
- replace the harness CJ11R AMM 73-21-50-000-002 and AMM 73-21-50-400-002.
- replace the VSV actuator AMM 75-32-10-000-001 and AMM 75-32-10-400-001.
B. If the test does not give the maintenance message VSV ACT, J11, ECU ENG2A:
Subtask 75-32-00-810-055-B ** ON A/C NOT FOR ALL - No maintenance action is required.
C. If the test gives the maintenance message VSV ACT, J11, ECU ENG2A:
Subtask 75-32-00-810-065-B ** ON A/C NOT FOR ALL - do a check for open or short to ground of the harness J11 between the ECU (4000KS) and the 6 o'clock junction box, between the 6 o'clock junction box and the VSV LVDT ASM 732518.
- repair the above wiring.
- disconnect the cable J11 from the ECU (4000KS) and do a resistance check of the cable J11 between:
. pins 12 and 28 (400 to 600 Ohms)
. pins 26 and 27 (100 to 180 Ohms)
. pins 10 and 25 (100 to 180 Ohms)
. pins 12 and 11 (> 10 Megohms)
. pins 26 and 11 (> 10 Megohms)
. pins 10 and 11 (> 10 Megohms)
. pin 12 and the ground (> 10 Megohms)
. pin 26 and the ground (> 10 Megohms)
. pin 10 and the ground (> 10 Megohms).
- replace the ECU [4000KS] AMM 73-21-60-000-001 and AMM 73-21-60-400-001.
- disconnect the cable J11 from the cable CJ11R at the 6 o'clock junction box and do a resistance check of the cable CJ11R between:
. pins 4 and 14 (400 to 600 Ohms)
. pins 1 and 6 (100 to 180 Ohms)
. pins 15 and 27 (100 to 180 Ohms)
. pins 4 and 5 (> 10 Megohms)
. pins 1 and 5 (> 10 Megohms)
. pins 15 and 5 (> 10 Megohms)
. pin 4 and the ground (> 10 Megohms)
. pin 1 and the ground (> 10 Megohms)
. pin 15 and the ground (> 10 Megohms).
- replace the harness J11 AMM 73-21-50-000-044 and AMM 73-21-50-400-044.
- disconnect the cable CJ11R from the VSV actuator and do a resistance check of the VSV actuator between:
. pins 2 and 3 (400 to 600 Ohms)
. pins 4 and 5 (100 to 180 Ohms)
. pins 6 and 7 (100 to 180 Ohms)
. pin 2 and the ground (> 10 Megohms)
. pin 4 and the ground (> 10 Megohms)
. pin 6 and the ground (> 10 Megohms).
- replace the harness CJ11R AMM 73-21-50-000-026 and AMM 73-21-50-400-026.
- replace the VSV actuator AMM 75-32-10-000-002 and AMM 75-32-10-400-002.
D. If the test does not give the maintenance message VSV ACT, J11, ECU ENG2A:
Subtask 75-32-00-710-061-A ** ON A/C NOT FOR ALL - No maintenance action is required.
E. Do the test given in Para. 3.A.