FWD Cabin Temperature uncontrollable or too low with TAV AMBER XX

TASK 21-63-00-810-856-A
FWD Cabin Temperature uncontrollable or too low with TAV AMBER XX

1. Possible Causes

TRIM VALVE FWD CAB [12HK]
wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 21-63-00-710-004	Operational Test of the Cockpit and Cabin Temperature Control with CFDS/MCDU
ASM 216302
AMM 21-63-51-000-001	Removal of the Trim Air Valve
AMM 21-63-51-400-001	Installation of the Trim Air Valve

3. Fault Confirmation
Subtask 21-63-00-710-141-A ** ON A/C NOT FOR ALL

A. Confirmation of the Fault
(1) Do the operational test of the cockpit and cabin temperature-control system AMM 21-63-00-710-004.

4. Fault Isolation
Subtask 21-63-00-810-150-A ** ON A/C NOT FOR ALL

A. If on the ECAM COND page the FWD trim air valve position indication shows amber XX and/or the FWD cabin temperature is uncontrollable or too low (in flight):

replace the TRIM VALVE FWD CAB [12HK] AMM 21-63-51-000-001 and AMM 21-63-51-400-001.

(1) If the fault continues:
(a) This wiring check is only applicable for Trim Air Valves previous to P/N 1320A0000-01 or 963B0000-01 or 750B0000-01.

do a check and repair the wiring ASM 216302 from:
the TRIM VALVE FWD CABIN (12HK) to the Zone Controller (8HK) and,
the TRIM VALVE FWD CABIN (12HK) to ground.

(b) This wiring check is only applicable for Trim Air Valves P/N 1320A0000-01 or 963B0000-01 or 750B0000-01 and subsequent.

do a check and repair the wiring ASM 216302 between:
TRIM VALVE FWD CABIN (12HK) connector A/U and ZC (8HK) connector AB/11A,
TRIM VALVE FWD CABIN (12HK) connector A/J and ZC (8HK) connector AB/10A,
TRIM VALVE FWD CABIN (12HK) connector A/K and ZC (8HK) connector AB/10B,
TRIM VALVE FWD CABIN (12HK) connector A/L and ZC (8HK) connector AB/11B,
TRIM VALVE FWD CABIN (12HK) connector A/C and ZC (8HK) connector AB/6C,
TRIM VALVE FWD CABIN (12HK) connector A/E and ZC (8HK) connector AB/6B,
the TRIM VALVE FWD CABIN (12HK) to ground.

Subtask 21-63-00-810-150-B ** ON A/C NOT FOR ALL

A. If on the ECAM COND page the FWD trim air valve position indication shows amber XX and/or the FWD cabin temperature is uncontrollable or too low (in flight):

replace the TRIM VALVE FWD CAB [12HK] AMM 21-63-51-000-001 and AMM 21-63-51-400-001.

(1) If the fault continues:

do a check and repair the wiring ASM 216302 from:
the TRIM AIR VALVE FWD CABIN (12HK) to the ACSC2 (57HH) and,
the TRIM AIR VALVE FWD CABIN (12HK) to ground.

Subtask 21-63-00-710-142-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:25:05 UTC