DOC AIRBUS | TSM A320FLoss of the TBV torque motor control through the channel B on Engine 2
TASK 75-26-00-810-808-A
Loss of the TBV torque motor control through the channel B on Engine 2
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 75-26-00-710-064-A ** ON A/C NOT FOR ALL
Subtask 75-26-00-810-057-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:37:06 UTC
Loss of the TBV torque motor control through the channel B on Engine 2
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| AMM 73-21-10-000-002 | Removal of the Hydromechanical Unit (HMU) |
| AMM 73-21-10-400-002 | Installation of the Hydromechanical Unit (HMU) |
| AMM 73-21-50-000-041 | Removal of the HJ8 Harness for SAC Engines |
| AMM 73-21-50-210-002 | Visual Inspection of the Wiring Harnesses |
| AMM 73-21-50-400-041 | Installation of the HJ8 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) |
| AMM 73-29-00-710-040 | Operational Test of the FADEC on the ground (with Engine Motoring) |
Subtask 75-26-00-710-064-A ** ON A/C NOT FOR ALL
A. Test
(1) Do the operational test of the FADEC 2B on the ground (with engine motoring) AMM 73-29-00-710-040.
4. Fault Isolation(1) Do the operational test of the FADEC 2B on the ground (with engine motoring) AMM 73-29-00-710-040.
Subtask 75-26-00-810-057-A ** ON A/C NOT FOR ALL
A. If the test gives the maintenance message J8, HMU(TBV TM), ECU:
disconnect the harness HJ8 from the J8 receptacle on the ECU (4000KS). Make sure that the electrical contacts of the J8 receptacle are not bent or have not moved AMM 73-21-50-210-002.
(1) If you find damage:
. pins 20 and 40 (1 to 150 Ohms)
. pins 20 and 39 (> 10 Megohms)
. pin 20 and the ground (> 10 Megohms).
(a) If the resistance values are in the specified limits:
Subtask 75-26-00-710-065-A ** ON A/C NOT FOR ALL disconnect the harness HJ8 from the J8 receptacle on the ECU (4000KS). Make sure that the electrical contacts of the J8 receptacle are not bent or have not moved AMM 73-21-50-210-002.
(1) If you find damage:
- replace the ECU [4000KS] , AMM 73-21-60-000-001 and AMM 73-21-60-400-001.
. pins 20 and 40 (1 to 150 Ohms)
. pins 20 and 39 (> 10 Megohms)
. pin 20 and the ground (> 10 Megohms).
(a) If the resistance values are in the specified limits:
- replace the ECU [4000KS] , AMM 73-21-60-000-001 and AMM 73-21-60-400-001.
- disconnect the harness HJ8 from the HMU and do a check of the HMU receptacle resistance between:
. pins 20 and 40 (1 to 150 Ohms)
. pins 20 and 39 (> 10 Megohms)
. pin 20 and the ground (> 10 Megohms).
- replace the harness HJ8 , AMM 73-21-50-000-041 and AMM 73-21-50-400-041.
- replace the HMU-2 [4000KC2] AMM 73-21-10-000-002 and AMM 73-21-10-400-002.
B. Do the test given in Para. 3.A.(1).