02/26/21
Message Overview:
Message Description:
Rudder Travel Limiter (RTL) disconnect fault detected by Horizontal Stabilizer Electronic Control Unit (HST ECU).
Possible Causes:
- Rudder Travel-Limiter Rotary Variable Differential Transformer (RTL RVDT) (MPE20)
- Rudder Travel-Limiter Actuator (RTLA) (MPE79)
- Horizontal-Stabilizer-Trim Electronic-Control Unit (HST ECU) (A130)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin:
- AW300-27-0077 - Troubleshooting Guide for Spoiler Electronic Control Unit and Horizontal Stabilizer Trim Electronic Control Unit (20501 - 20999)
- AW300-27-0081 - Spoiler Electronic Control Unit (SECU) and Horizontal Stabilizer Electronic Control Unit (HSTECU) - Cold Temperature Circuit Breaker Reset Procedure (20501 - 20999)
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| Removal of the Junction Box JB1 | AMM 24-63-01-000-802 |
| Installation of the Junction Box JB1 | AMM 24-63-01-400-802 |
| Removal of the Junction Box JB1 Circuit-Cards | AMM 24-63-01-000-803 |
| Installation of the Junction Box JB1 Circuit-Cards | AMM 24-63-01-400-803 |
| Functional Test of Junction Box JB1 | AMM 24-63-01-720-801 |
| Detailed Inspection of the Rudder Travel Limiter | AMM 27-21-00-220-804 |
| Removal of the Rudder Travel Limiter Actuator | AMM 27-21-28-000-801 |
| Installation of the Rudder Travel Limiter Actuator | AMM 27-21-28-400-801 |
| Operational Test of the Rudder Travel Limiter Actuator | AMM 27-21-28-710-801 |
| Electrical Rigging of the Rudder Travel Limiter Actuator | AMM 27-21-28-820-801 |
| Removal of the Rudder Travel-Limiter Rotary Variable-Differential Transformer (RVDT) | AMM 27-21-29-000-801 |
| Installation of the Rudder Travel-Limiter Rotary Variable-Differential Transformer (RVDT) | AMM 27-21-29-400-801 |
| Electrical Rigging of the Rudder Travel-Limiter Rotary Variable-Differential Transformer (RVDT) | AMM 27-21-29-820-801 |
| Removal of the Horizontal Stabilizer-Trim Actuator (HSTA) | AMM 27-41-05-000-801 |
| Installation of the Horizontal Stabilizer-Trim Actuator (HSTA) | AMM 27-41-05-400-801 |
| Operational Test of the Horizontal Stabilizer-Trim Actuator (HSTA) Full Range Trimming | AMM 27-41-05-710-801 |
| Functional Test of the HSTA Torque Limiter | AMM 27-41-05-720-801 |
| Removal of the Horizontal-Stabilizer-Trim Electronic-Control Unit (HST ECU) | AMM 27-41-21-000-801 |
| Installation of the Horizontal-Stabilizer-Trim Electronic-Control Unit (HST ECU) | AMM 27-41-21-400-801 |
| Operational Test of the Horizontal-Stabilizer-Trim Electronic-Control Unit (HST ECU) | AMM 27-41-21-710-801 |
| Removal of the Input/Output Concentrator Unit (IOC) | AMM 31-45-05-000-801 |
| Installation of the Input/Output Concentrator Unit (IOC) | AMM 31-45-05-400-801 |
| Operational Test of the Input/Output Concentrator Unit (IOC) | AMM 31-45-05-710-801 |
| Wiring - Maintenance Practices - ALL | SPM 20-12-00-02 |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 |
| Electrical Connectors - Maintenance Practice - ALL | SPM 20-20-00-02 |
Troubleshooting Recommendations:
- Reset the following circuit breakers with L Hyd, R Hyd and AUX Hyd pressurized.
PRI STAB TRIM/RUD LIM CB1-B15 SEC STAB TRIM/RUD LIM CB2-B13 NOTE: Keep circuit breakers pulled for 10 seconds.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Do Detailed Inspection of the Rudder Travel Limiter. Replace/repair as required.
- Do Operational Test of the Rudder Travel-Limiter Actuator.
- If test passes, do close out.
- If test fails, continue with next step.
- Do Electrical Rigging of the Rudder Travel-Limiter Actuator.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Do wiring check between RTLA connectors, HST ECU connectors, RTL RVDT connector. Repair/replace as required.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Check RTL RVDT internal wiring for continuity, short-circuit and insulation.
- If RTL RDVT internal wiring is confirmed good, go to step 8.
- If RTL RVDT internal wiring is not good, continue with next step.
- Replace RTL RVDT.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Replace RTLA.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Replace HST ECU.
- Do close out.