DOC AIRBUS | TSM A320FRCDR/GND CTL Pushbutton - Blue ON Indicator Light does not come on
TASK 31-33-00-810-824-A
RCDR/GND CTL Pushbutton - Blue ON Indicator Light does not come on
1. Possible Causes
A. Referenced Information
3. Fault Confirmation
Subtask 31-33-00-710-066-A
Subtask 31-33-00-810-058-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:30:01 UTC
RCDR/GND CTL Pushbutton - Blue ON Indicator Light does not come on
1. Possible Causes
- P/BSW - RCDR/GND CTL [11TU]
control relay (13TU) control relay (12TU) diode (1162VD) - SW-LOW OIL PRESS [4000EN]
- EIU-1 [1KS1]
- RELAY-OIL LOW PRESS AND GROUND, ENG 1 [12KS1]
- EIU-2 [1KS2]
- RELAY-OIL LOW PRESS AND GROUND, ENG 2 [12KS2]
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 33-14-00-810-801-A | Failure of One Annunciator Light Only |
| TSM TASK 73-25-00-810-849-A | Failure of the Oil Low Pressure and Ground Relay on Engine 1 |
| TSM TASK 73-25-00-810-850-A | Failure of the Low Oil Pressure and Ground Relay on Engine 2 |
| AMM 31-33-00-710-001 | Operational Test of the Power Interlocks and Status Monitoring |
| ASM 313301 | |
| ASM 732509 | |
| AMM 79-34-15-000-040 | Removal of the Low Oil Pressure Switch |
| AMM 79-34-15-400-040 | Installation of the Low Oil Pressure Switch |
| ASM 793601 |
Subtask 31-33-00-710-066-A
A. Test
(1) Do the operational test of the power interlocks and status monitoring AMM 31-33-00-710-001.
4. Fault Isolation(1) Do the operational test of the power interlocks and status monitoring AMM 31-33-00-710-001.
Subtask 31-33-00-810-058-A ** ON A/C NOT FOR ALL
A. Procedure
ASM 313301
(1) If the blue ON indicator light of the RCDR/GND CTL pushbutton does not come on:
(a) Do a check for 28VDC at the RCDR/GND CTL pushbutton (11TU) connector A/A3.
(b) If there is no 28VDC at the RCDR/GND CTL pushbutton (11TU) connector A/A3:
(a) Do a check for 28VDC at the control relay (12TU) connector A/X.
(b) If there is no 28VDC, at the control relay (12TU) connector A/X:
(a) Do a check for GROUND at the control relay (12TU) connector A/Z.
(b) If there is GROUND at the control relay (12TU) connector A/Z:
(a) Do a check for GROUND at the diode (1162VD) connector A/5.
(b) If there is GROUND at the diode (1162VD) connector A/5:
Subtask 31-33-00-810-058-B ** ON A/C NOT FOR ALL ASM 313301
(1) If the blue ON indicator light of the RCDR/GND CTL pushbutton does not come on:
- Do the trouble shouting procedure of the annunciator lights in the cockpit (Ref. TSM TASK 33-14-00-810-801).
(a) Do a check for 28VDC at the RCDR/GND CTL pushbutton (11TU) connector A/A3.
(b) If there is no 28VDC at the RCDR/GND CTL pushbutton (11TU) connector A/A3:
- Replace the P/BSW - RCDR/GND CTL [11TU] .
(a) Do a check for 28VDC at the control relay (12TU) connector A/X.
(b) If there is no 28VDC, at the control relay (12TU) connector A/X:
- Replace the
control relay (13TU) .
(a) Do a check for GROUND at the control relay (12TU) connector A/Z.
(b) If there is GROUND at the control relay (12TU) connector A/Z:
- Replace the
control relay (12TU) .
(a) Do a check for GROUND at the diode (1162VD) connector A/5.
(b) If there is GROUND at the diode (1162VD) connector A/5:
- Replace the
diode (1162VD)
- Do the trouble shouting procedure of the oil low press and ground discrete output on EIU1 and/or EIU 2 (Ref. TSM TASK 73-25-00-810-849) and/or (Ref. TSM TASK 73-25-00-810-850).
A. Procedure ASM 313301, ASM 732509 and ASM 793601
(1) If the blue ON indicator light of the RCDR/GND CTL pushbutton does not come on:
(a) Do a check for 28VDC at the RCDR/GND CTL pushbutton (11TU) connector A/A3.
(b) If there is no 28VDC at the RCDR/GND CTL pushbutton (11TU) connector A/A3:
(a) Do a check for 28VDC at the control relay (12TU) connector A/X.
(b) If there is no 28VDC at the control relay (12TU) connector A/X:
(a) Do a check for GROUND at the control relay (12TU) connector A/Z.
(b) If there is GROUND at the control relay (12TU) connector A/Z:
(a) Do a check for GROUND at the diode (1162VD), connector A/5.
(b) If there is GROUND at the diode (1162VD), connector A/5:
(a) Do a check for GROUND at the switch (4000EN), connector A/3.
(b) If there is GROUND at the switch (4000EN), connector A/3:
Subtask 31-33-00-710-067-A (1) If the blue ON indicator light of the RCDR/GND CTL pushbutton does not come on:
- Do the trouble shouting procedure of the annunciator lights in the cockpit (Ref. TSM TASK 33-14-00-810-801).
(a) Do a check for 28VDC at the RCDR/GND CTL pushbutton (11TU) connector A/A3.
(b) If there is no 28VDC at the RCDR/GND CTL pushbutton (11TU) connector A/A3:
- Replace the P/BSW - RCDR/GND CTL [11TU] .
(a) Do a check for 28VDC at the control relay (12TU) connector A/X.
(b) If there is no 28VDC at the control relay (12TU) connector A/X:
- Replace the
control relay (13TU) .
(a) Do a check for GROUND at the control relay (12TU) connector A/Z.
(b) If there is GROUND at the control relay (12TU) connector A/Z:
- Replace the
control relay (12TU) .
(a) Do a check for GROUND at the diode (1162VD), connector A/5.
(b) If there is GROUND at the diode (1162VD), connector A/5:
- Replace the
diode (1162VD) .
(a) Do a check for GROUND at the switch (4000EN), connector A/3.
(b) If there is GROUND at the switch (4000EN), connector A/3:
- Replace the SW-LOW OIL PRESS [4000EN] AMM 79-34-15-000-040 and AMM 79-34-15-400-040.
- Do the trouble shouting procedure of the oil low press and ground discrete output on EIU-1 [1KS1] , RELAY-OIL LOW PRESS AND GROUND, ENG 1 [12KS1] and/or EIU-2 [1KS2] , RELAY-OIL LOW PRESS AND GROUND, ENG 2 [12KS2] (Ref. TSM TASK 73-25-00-810-849) and (Ref. TSM TASK 73-25-00-810-850).
B. Do the test given in paragraph 3.A. again.