Intermittent Indication of HYD B RSVR LO LVL and HYD B RSVR OVHT on ECAM DU

TASK 29-12-00-810-814-A
Intermittent Indication of HYD B RSVR LO LVL and HYD B RSVR OVHT on ECAM DU

1. Possible Causes

SDAC-1 [1WV1]
SDAC-2 [1WV2]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 29-12-00-810-802-A	Overheat Indication of the Blue Hydraulic System
TSM TASK 29-12-00-810-803-A	Loss of the Correct Quantity in the Blue Hydraulic Reservoir
AMM 24-41-00-861-002	Energize the Aircraft Electrical Circuits from the External Power
AMM 31-55-34-000-001	Removal of the SDAC
AMM 31-55-34-400-001	Installation of the SDAC
AMM 31-60-00-860-001	EIS Start Procedure

3. Fault Confirmation
Subtask 29-12-00-865-060-A

A. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	HYD/HYD PWR/B WARN/& CTL	2702GJ	C12
49VU	SDAC/1 AND 2/28VDC/ESS BUS	12WV	F05
49VU	SDAC/1/SPLY	3WV	F04
49VU	SDAC/2/26VAC SYNC/AC ESS BUS	6WV	F03
49VU	SDAC/1/26VAC SYNC/AC ESS BUS	5WV	F02
** ON A/C NOT FOR ALL
121VU	EIS/SDAC/1/BUS1/26VAC SYNC AC	9WV	Q04
** ON A/C ALL
121VU	HYDRAULIC/LOW/LVL/IND	1832GQ	N32
121VU	HYDRAULIC/HYD/QTY/IND	1831GQ	P35
121VU	EIS/SDAC/2/SPLY	2WV	Q06
121VU	EIS/SDAC/2/BUS1/26VAC SYNC AC	10WV	Q05
121VU	EIS/SDAC/1/BUS2/26VAC SYNC AC	7WV	Q03
121VU	EIS/SDAC/2/BUS2/26VAC SYNC AC	8WV	Q02

Subtask 29-12-00-860-065-A

B. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
(2) Do the EIS start procedure (Upper ECAM DU and lower ECAM DU only)
AMM 31-60-00-860-001.
(3) Look for fault indications on the upper ECAM DU.

4. Fault Isolation
Subtask 29-12-00-810-066-A ** ON A/C NOT FOR ALL

A. If the Fault Confirmation gives:

-the messages HYD B RSVR LO LVL and HYD B RSVR on the upper ECAM DU:

Open these circuit breakers:
- 3WV,
- 5WV,
- 7WV and
- 9WV.

(1) If the fault messages go off:

replace the SDAC-1 [1WV1] AMM 31-55-34-000-001 and AMM 31-55-34-400-001.

(2) If the fault continues:
(a) Close these circuit breakers:
- 3WV,
- 5WV,
- 7WV and
- 9WV.
(b) Open these circuit breakers:
- 2WV,
- 6WV,
- 8WV and
- 10WV.
(3) If the fault messages go off:

replace the SDAC-2 [1WV2] AMM 31-55-34-000-001 and AMM 31-55-34-400-001.

(4) If the fault continues:

Do the troubleshooting as given in the subsequent references:
- (Ref. TSM TASK 29-12-00-810-803) and
- (Ref. TSM TASK 29-12-00-810-802).

Subtask 29-12-00-810-066-B ** ON A/C NOT FOR ALL

A. If the Fault Confirmation gives:

-the messages HYD B RSVR LO LVL and HYD B RSVR on the upper ECAM DU:

Open these circuit breakers:
- 3WV,
- 5WV,
- 7WV and
- 1832GQ.

(1) If the fault messages go off:

replace the SDAC-1 [1WV1] AMM 31-55-34-000-001 and AMM 31-55-34-400-001.

(2) If the fault continues:
(a) Close these circuit breakers:
- 3WV,
- 5WV,
- 7WV and
- 1832GQ.
(b) Open these circuit breakers:
- 2WV,
- 6WV,
- 8WV and
- 10WV.
(3) If the fault messages go off:

replace the SDAC-2 [1WV2] AMM 31-55-34-000-001 and AMM 31-55-34-400-001.

(4) If the fault continues:

Do the troubleshooting as given in these references:
- (Ref. TSM TASK 29-12-00-810-803) and
- (Ref. TSM TASK 29-12-00-810-802).

Subtask 29-12-00-860-066-A

B. Do the fault confirmation procedure as given in Para. 3. to make sure that the operation is correct.

[Rev.8 from Aug 2018] 2026.04.04 04:29:23 UTC