Loss of the CVR Data Detected by the ATSU

TASK 46-21-00-810-859-A
Loss of the CVR Data Detected by the ATSU

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
ESPM 2052210
AWM 237105
AMM 23-71-35-000-001	Removal of the Cockpit Voice Recorder (CVR) 1RK
AMM 23-71-35-400-001	Installation of the Cockpit Voice Recorder (CVR) 1RK
AMM 46-21-00-740-001	BITE Test of the ATIMS
AMM 46-21-34-000-001	Removal of the Air Traffic Service Unit (ATSU)
AMM 46-21-34-400-001	Installation of the Air Traffic Service Unit (ATSU)

3. Fault Confirmation
Subtask 46-21-00-740-160-C ** ON A/C NOT FOR ALL

A. Test
(1) Do the BITE test of the ATIMS AMM 46-21-00-740-001.

4. Fault Isolation
Subtask 46-21-00-810-108-C ** ON A/C NOT FOR ALL

A. If the test confirms the fault:
(1) Replace the CVR [1RK] AMM 23-71-35-000-001 and AMM 23-71-35-400-001.
(a) If the fault continues:

1 If the fault continues:
a Do a check and repair the wiring between:

The pins A/50 and 51 of the CVR (1RK) and the pins AA/5K and 5J of the ATSU (1TX1) AWM 237105 ESPM 2052210
The pins A/33 and 34 of the CVR (1RK) and the pins AB/1F and 1E of the ATSU (1TX1) AWM 237105 ESPM 2052210.

Subtask 46-21-00-740-161-C ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:34:22 UTC