# JASC 2917: Hydraulic Pressure Regulator, Main

- Type: JASC system/component code (FAA)
- ATA chapter: 29 Hydraulic Power
- Title in the code table: HYDRAULIC PRESSURE REGULATOR, MAIN
- Service difficulty reports: 65
- FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=29
- Page: https://openairdocs.org/jasc/2917

## What it covers

The unit that maintains a preset operating system pressure to the using systems. Typical parts are regulator, seal, case, etc.

## Service difficulty reports (65, newest 50)

- [SDR FDEA202208101954](https://openairdocs.org/sdr/FDEA202208101954), Aug 10, 2022: Boeing 757200. TRACK. LEAKING. PDIS 912 29-02 3898 10AUG22 TLV OPEN U LOGPAGES:3336064 UPON REACHING CRUISE FL380 THE '' R HYD QTY'' MESSAGE APPEARED R (N912FD)
- [SDR CALA2019101401756](https://openairdocs.org/sdr/CALA2019101401756), Oct 14, 2019: Boeing 767322. PRESSURE SWITCH. INOPERATIVE. HYD SYS PRESS R EICAS CAUTION CAME ON IN FLIGHT DEBRIEF CREW RIGHT ELEC PRESS LIGHT FLICKERED AND SYS PRESS LIGH T ILLUM (N657UA)
- [SDR SWIA2019073046100](https://openairdocs.org/sdr/SWIA2019073046100), Jul 30, 2019: Cndair CL6002B19. PRESSURE SWITCH. FAILED. HYD 3 LOW PRESSURE ON CLIMB OUT. FLT 5283. REMOVED AND REPLACED THE HYD 3A LOW-PRESSURE SWITCH S9DB IAW AMM. OPS CHECK G (N980SW)
- [SDR CA190731019](https://openairdocs.org/sdr/CA190731019), Jul 29, 2019: Agusta AW139. CONTROL MODULE. CRACKED. (CAN) NO. 2 HYDRAULIC PRESSURE CONTROL MODULE (PCM) DISCOVERED WITH A CRACK ON THE NUMBER 4 HYDRAULIC PUMP SUCTION BOX O
- [SDR AALA201903199004](https://openairdocs.org/sdr/AALA201903199004), Mar 18, 2019: Airbus A321231. PRESSURE SWITCH. MALFUNCTIONED. A HYD Y NR 2 ENGINE PUMP LOW PRESSURE ECAM OCCURRED AFTER TAKEOFF. RETURNED AND LANDED. THE AIRCRAFT WAS GROUNDED. MAINT (N986AN)
- [SDR YENA20140409072](https://openairdocs.org/sdr/YENA20140409072), Apr 9, 2014: Airbus A320232. PRESSURE SWITCH. FAILED. DECLARED AN EMERGENCY AND ACFT RETURNED TO DEPARTURE, FOR A HYD GREEN RESERVOIR LOW AIR PRESSURE ECAM DURING CRUISE. GRE (N529JB)
- [SDR V6NA20131226001](https://openairdocs.org/sdr/V6NA20131226001), Dec 26, 2013: Lear 60LEAR. REGULATOR VALVE. CHATTERING. WHILE EN ROUTE AT FL 41, AMBER, R HYD PRESS LIGHT ILLUMINATED. NOTIFIED MX & CONTINUED TO DESTINATION. ON APPROACH, BEGA (N296L)
- [SDR CA130124006](https://openairdocs.org/sdr/CA130124006), Jan 24, 2013: Boeing 7572B7. BYPASS VALVE. FAILED. (CAN) DURING SERVICE CHECK FOUND HYDRAULIC FLUID LEAKING FROM BYPASS ELEVATOR PRESSURE REDUCER VALVE. FURTHER INSPECTION
- [SDR UALA2012021000802](https://openairdocs.org/sdr/UALA2012021000802), Feb 10, 2012: Boeing 777222. TRANSDUCER. FAULTY. C2 PUMP PRESS OUT-RANGE AHM IS HITTING ON ALL LEGS FOR MSG 29-10570, ACMP C2 OUTPUT PRESSURE IS OUT OF RANGE. THIS IS ON (N772UA)
- [SDR C2XA11RI116](https://openairdocs.org/sdr/C2XA11RI116), Jun 26, 2011: Emb EMB145LR. PRESSURE SWITCH. DEFECTIVE. FLIGHT 5923 - RIC - FLIGHT CREW REPORTED ENGINE 1 HYDRAULIC PUM FAILED. CREW PERFORMED AIR RETURN AND LANDED UNEVENTFULL (N15912)
- [SDR UALA2011010300039](https://openairdocs.org/sdr/UALA2011010300039), Jan 2, 2011: Boeing 777222. CHECK VALVE. FAULTY. CENTER ADP C1 MODULE RPL. DUE TO PREVIOUS FAILURE OF THE PRESSURE TRANSDUCER CHECK VALVE IN THE FILTER MODULE, AS A PREC (N771UA)
- [SDR U5QA06028](https://openairdocs.org/sdr/U5QA06028), Dec 26, 2010: Lear 60LEAR. REGULATOR. FAILED. AIRCRAFT DEPARTED KSUA TO MMTO. SHORTLY AFTER REACHING CRUISE ALTITUDE (FL430), RIGHT HYD PRES LIGHT ILLUMINATED AND THE (N869AV)
- [SDR USAA20100706BA030](https://openairdocs.org/sdr/USAA20100706BA030), Jul 4, 2010: Airbus A330243. DAMPER. LEAKING. MAN - FLT 787 EN ROUTE CDG TO CLT. RECEIVED HYD GREEN ENG 1 & 2 LOW PRESS MESSAGE DURING FLIGHT. THE FLIGHT WAS DIVERTED (N281AY)
- [SDR CA100528008](https://openairdocs.org/sdr/CA100528008), May 27, 2010: Cvac 340CVAC. REGULATOR. BROKEN. (CAN) AFTER PRACTICE FIRE MISSION (PRACTICE WATER DROP) FLAPS WOULD NOT COME UP BUT REMAINED STUCK IN THE FULL DOWN POSI
- [SDR CA091021015](https://openairdocs.org/sdr/CA091021015), Oct 19, 2009: Snias AS350B1. PRESSURE SWITCH. INOPERATIVE. (CAN) A/C HAD JUST CLEARED CONTROL ZONE , WHEN THE HYDRAULIC HORN AND HYDR. LIGHT ACTIVATED, HYD ISOLATION SWITCHED OFF 
- [SDR U5QA06020](https://openairdocs.org/sdr/U5QA06020), Oct 4, 2009: Lear 60LEAR. REGULATOR. FAILED. AT FL410 L HYD PRESS AMBER ANNUNCIATOR ILLUMINATED. R HYD PRESS AMBER ANNUNCIATOR ILLUMINATED APPROX 15 MINUTES LATER. H (N869AV)
- [SDR U5QA06017](https://openairdocs.org/sdr/U5QA06017), Apr 29, 2009: Lear 60LEAR. REGULATOR. PLUGGED. AT CRUISE BOTH AMBER HYDRAULIC PRESSURE LOW LIGHTS ILLUMINATED. CHANGED DESTINATION TO BDL. TAXIED AIRCRAFT TO BOMBARDIE (N27ZH)
- [SDR HNAA2008120700340](https://openairdocs.org/sdr/HNAA2008120700340), Dec 7, 2008: Dhav DHC8102. REGULATOR. FAILED. JUST AFTER TAKEOFF, THE 'RUDDER FULL PRESSURE', 'RUDDER PRESSURE', AND 'NR 2 RUDDER HYDRAULIC' CAUTION LIGHTS CAME ON. H (N846EX)
- [SDR AALA200802516A](https://openairdocs.org/sdr/AALA200802516A), Nov 12, 2008: Boeing 767323. PRESSURE SWITCH. FAULTED. INFLIGHT - LEFT HYDRAULIC SYSTEM LOW PRESSURE INDICATION. RETURNED TO JFK AND LANDED WITHOUT INCIDENT. REPLACED LEFT HYD (N39364)
- [SDR TSAA0729066](https://openairdocs.org/sdr/TSAA0729066), Dec 16, 2007: Boeing 737236. REGULATOR. MALFUNCTIONED. FLIGHT 208 HNL-OGG - UPON RETRACTION OF THE LANDING GEAR AND FLAPS, THE CREW NOTED A LOUD FLUTTERING NOISE AND BUFFET. C (N828AL)
- [SDR CA071210006](https://openairdocs.org/sdr/CA071210006), Dec 7, 2007: Snias AS350B2. CONTROLLER. MALFUNCTIONED. (CAN) DURING FIRST GROUND RUN FOLLOWING A MAJOR 12 YEAR INSP, THERE WAS SIGNIFICANT HYDR FLUID LOSS IN THE AREA OF THE M
- [SDR NSVA20070228](https://openairdocs.org/sdr/NSVA20070228), Sep 16, 2007: Saab 340B. PRESSURE SWITCH. MALFUNCTIONED. HYDRAULIC LIGHT ILLUMINATED AT ALT COMPLETED APPROPRIATE CHECK LIST DETERMINED THAT ATO FUNCTION FAILED MAIN ACCUMULATOR (N343CJ)
- [SDR TSAA0729017](https://openairdocs.org/sdr/TSAA0729017), Apr 26, 2007: Boeing 737236. REGULATOR. UNKNOWN. FLT 107 HNL-LIH - LOUD FLUTTER HEARD ON ROTATION. CONTINUED TO 2000 FT. RETURNED FOR LANDING. AIRCRAFT TAXIED TO GATE AT (N828AL)
- [SDR CA070402003](https://openairdocs.org/sdr/CA070402003), Mar 22, 2007: Pilats PC1245. PRESSURE SWITCH. LEAKING. (CAN) DURING INSPECTION IT WAS NOTED THAT THIS HYDRAULIC PRESSURE SWITCH WAS LEAKING FLUID AT THE SWAGED SEEM OF THE SWI
- [SDR UPS06548739](https://openairdocs.org/sdr/UPS06548739), Dec 8, 2006: Boeing 75724APF. PRESSURE SWITCH. FAILED. INSPECTION TYPE:N/A ATB - AFTER DEPARTURE THE CREW EXPERIENCED A HYD SYS PUMP FAILURE. THE A/C RETURNED TO SDF. NO EMERG (N459UP)
- [SDR QXEA200602961](https://openairdocs.org/sdr/QXEA200602961), Nov 12, 2006: Bombdr DHC8402. SWITCH. MALFUNCTIONED. BOI FLIGHT NR 2303: AFTER START, NR 3 HYD PUMP CAUTION LIGHT REMAINED ILLUMINATED. WHEN NR 3 ISO VALVE SWITCH 'OPEN' HYD (N425QX)
- [SDR AWXA200601801](https://openairdocs.org/sdr/AWXA200601801), Oct 21, 2006: Airbus A320231. ACCUMULATOR. LEAKING. FLIGHT 281; PHX - SJC - IN CRUISE FLIGHT, THE A/C LOST YELLOW HYDRAULIC PRESSURE AND QUANTITY INDICATION. THE CREW DIVER (N621AW)
- [SDR HEEA109638](https://openairdocs.org/sdr/HEEA109638), Jun 13, 2006: Bell 214ST. PRESSURE SWITCH. MALFUNCTIONED. DURING CRUISE FLIGHT THE NR 1 HYD CAUTION LIGHT CAME ON. PERFORMED THE EMERGENCY CHECKLIST AND THEN DEVIATED TO FOU. MAI (N8045T)
- [SDR DL738050021](https://openairdocs.org/sdr/DL738050021), Jan 10, 2005: Boeing 737832. MODULE. CONTAMINATED. ENG 1 AND ENG 2 HYD PUMPS LOW PRESS LIGHTS ILLUM IN FLT. FOUND EVIDENCE OF MOISTURE/WATER IN HYD RSVR PRESS MOD. DISCONN (N3766)
- [SDR MUY2004F00000](https://openairdocs.org/sdr/MUY2004F00000), Jul 14, 2004: Piper PA32301T. PRESSURE SWITCH. LEAKING. HYDAULIC PRESSURE SWITCH LEAKS INTERNALLY. LEAK IS VERY SLOW. OVER AN EXTENDED PERIOD OF TIME, HYDRAULIC RESEVOIR IS DEP (N4355Y)
- [SDR DL73S040191](https://openairdocs.org/sdr/DL73S040191), Feb 25, 2004: Boeing 737232. REGULATOR. LEAKING. LOSS OF A-SYSTEM HYDRAULIC PRESSURE. FOUND NO RESERVOIR HEAD PRESSURE. REPLACED RESERVOIR PRESSURE REGULATOR AND BOTH CH (N329DL)
- [SDR AWXA200301066](https://openairdocs.org/sdr/AWXA200301066), Sep 21, 2003: Airbus A320232. PRESSURE SWITCH. FAILED. ON CLIMBOUT OF PHX EN ROUTE FOR SNA RECEIVED ECAM GREEN HYDRAULIC PUMP LOW PRESSURE INDICATION, TURNED BACK TO PHX AND L (N647AW)
- [SDR BAQA087117](https://openairdocs.org/sdr/BAQA087117), Aug 4, 2003: Aerosp AS365N2. PRESSURE SWITCH. INOPERATIVE. HYD SYSTEM PRESSURE SWITCH INOPERATIVE. REPLACED WITH SERVICEABLE UNIT. (N915ME)
- [SDR TSAA0329044](https://openairdocs.org/sdr/TSAA0329044), Mar 9, 2003: Boeing 73776N. PRESSURE SWITCH. FAILED. AFTER TAKEOFF THE 'A' SYSTEM HYDRAULIC PUMP LIGHT CAME ON. THE AIRCRAFT RETURNED TO HNL AND MADE AN OVERWEIGHT LANDING W (N744AL)
- [SDR FTU2003F00003](https://openairdocs.org/sdr/FTU2003F00003), Feb 14, 2003: Gulstm 695A. REGULATOR. FAILED. HYDRAULIC REGULATOR WAS INSTALLED IN THIS AIRCRAFT AS A OVERHAULED, EXCHANGED. THIS UNIT FAILED DURING TAKEOFF, WHICH PR (N79PH)
- [SDR MALA020691](https://openairdocs.org/sdr/MALA020691), Dec 26, 2002: Bac AVRO146RJ85A. REGULATOR. ACTIVATED. DURING FLIGHT 3641, AIR LOW PRESSURE ON YELLOW HYDRAULIC SYSTEM ILLUMINATED. AIR RETURN TO MSP. MAINTENANCE REPLACED PSI (N512XJ)
- [SDR SWAA022932](https://openairdocs.org/sdr/SWAA022932), Dec 13, 2002: Boeing 7377H4. MODULE. LEAKING. AIR TURNBACK, DECLARED EMERGENCY, SLIGHT HYDRAULIC SMELL DURING TAXI, STRONG HYDRAULIC SMELL AT HIGH POWER DURING TAKEOF (N718SW)
- [SDR KBMA116009](https://openairdocs.org/sdr/KBMA116009), Sep 12, 2002: Snias AS350BA. PRESSURE SWITCH. INOPERATIVE. HYDRAULIC WARNING LIGHT STAYS ILLUMINATED ON THE GROUND AT FLIGHT IDLE. REPLACED HYD SWITCH WITH NEW SWITCH. (N350SH)
- [SDR CA020327004](https://openairdocs.org/sdr/CA020327004), Mar 20, 2002: Pilats PC1245. PRESSURE SWITCH. FAILED. (CAN) AFTER TAKEOFF, REPORTED THE HYDRAULIC PUMP SEEMED TO RUN LONGER THAN NORMAL, AND THAT THE UNDER FLOOR HEATER WAS N
- [SDR CA020314001](https://openairdocs.org/sdr/CA020314001), Mar 12, 2002: Beech 200BEECH. PRESSURE SWITCH. STICKS. (CAN) AFTER TAKEOFF THE HYDRAULIC PUMP CYCLED ON FOR AN ABNORMAL LENGTH OF TIME WITH THE GEAR SELECTED TO THE UP POSITIO
- [SDR OLJ2001F00001](https://openairdocs.org/sdr/OLJ2001F00001), Aug 12, 2001: Aerosp SA365N1. PRESSURE SWITCH. INOPERATIVE. AUX HYDRAULIC ILLUMINATED DURING CRUISE FLIGHT. PILOT PERFORMED A PRECAUTIONARY LANDING. MAINTENANCE WAS DISPATCHED TO T (N65CW)
- [SDR EISA20000198](https://openairdocs.org/sdr/EISA20000198), Nov 1, 2000: Boeing 727225. RELIEF VALVE. INOPERATIVE. CLIMBING OUT OF 1000 FT HYDRAULIC A SYSTEM PRESSURE FAILED, RAN APPROPRIATE CHECKLIST AND RETURNED TO (TUS). REPLACED A  (N352PA)
- [SDR CA001030016](https://openairdocs.org/sdr/CA001030016), Oct 12, 2000: Pilats PC1245. PRESSURE SWITCH. LEAKING. (CAN) HYDRAULIC PUMP WOULD RUN CONSTANTLY IN-FLIGHT AND ON GROUND WITH ASSOCIATED HYD AMBER LIGHT ON THE CAWS PANEL (CEN
- [SDR ERYA682D1](https://openairdocs.org/sdr/ERYA682D1), Oct 6, 2000: Lear 35A. REGULATOR VALVE. FAILED. HYDRAULIC FAILURE. (N924AM)
- [SDR 2000UALA00515](https://openairdocs.org/sdr/2000UALA00515), Aug 26, 2000: Airbus A320232. SWITCH. FAILED. B-HYDRAULIC PUMP LOW PRESSURE INDICATION. *S/D* REPLACED PRESS SWITCH FOR BLUE ELECTRIC PUMP. (N419UA)
- [SDR SIMA1788](https://openairdocs.org/sdr/SIMA1788), Jun 26, 2000: Saab 340B. PRESSURE SWITCH. INOPERATIVE. LRD - FLT 3285 - WHILE IN CRUISE FLIGHT HYD MASTER CAUTION LIGHT CAME ON. PERFORMED MEMORY ITEMS AND RAN QRH CHECKLIST.  (N904AE)
- [SDR 2000UALA00312](https://openairdocs.org/sdr/2000UALA00312), Jun 5, 2000: Airbus A319131. PRESSURE SWITCH. LEAKING. GREEN HYDRAULIC SYSTEM LOSS IN CRUISE. QUANTITY AND PRESSURE READING ZERO. *S/D* CHECKED NR 1 ENGINE FOR EXTERNAL HYDRAU (N821UA)
- [SDR SIMA1471](https://openairdocs.org/sdr/SIMA1471), May 26, 2000: Saab 340B. PRESSURE SWITCH. FAILED. LFT - FLT 3355 - HYDRAULIC CENTRAL WARNING PANEL LIGHT WITH MAIN AND EMERGENCY PRESSURE. LANDING GEAR EMERGENCY HANDLE P (N901AE)
- [SDR 20000511SH041](https://openairdocs.org/sdr/20000511SH041), Apr 26, 2000: Lear 24A. REGULATOR. LEAKING. AIRCRAFT EXPERIENCED HYDRAULIC PRESSURE LOSS. EMERGENCY GEAR EXTENSION WAS PERFORMED AND AN UNEVENTFUL LANDING ACCOMPLIS (N93BP)
- [SDR 2000UALA00198](https://openairdocs.org/sdr/2000UALA00198), Apr 17, 2000: Boeing 767322. O-RING. LEAKING. CENTER HYDRAULIC FLUID LOSS. AMBER ALERT. DIVERTED ORD. *S/D* FOUND FLUID LEAKING FROM CENTER PUMP FILTER MODULE DELTA P (N642UA)

All 65: https://openairdocs.org/jasc/2917/reports.md

## Other codes in chapter 29

- [JASC 2900](https://openairdocs.org/jasc/2900): Hydraulic Power System (333 reports)
- [JASC 2910](https://openairdocs.org/jasc/2910): Hydraulic System, Main (11,280 reports)
- [JASC 2911](https://openairdocs.org/jasc/2911): Hydraulic Power Accumulator, Main (202 reports)
- [JASC 2912](https://openairdocs.org/jasc/2912): Hydraulic Filter, Main (201 reports)
- [JASC 2913](https://openairdocs.org/jasc/2913): Hydraulic Pump (Electric/Engine), Main (4,062 reports)
- [JASC 2914](https://openairdocs.org/jasc/2914): Hydraulic Handpump, Main (22 reports)
- [JASC 2915](https://openairdocs.org/jasc/2915): Hydraulic Pressure Relief Valve, Main (101 reports)
- [JASC 2916](https://openairdocs.org/jasc/2916): Hydraulic Reservoir, Main (385 reports)
- [JASC 2920](https://openairdocs.org/jasc/2920): Hydraulic System, Auxiliary (287 reports)
- [JASC 2921](https://openairdocs.org/jasc/2921): Hydraulic Accumulator, Auxiliary (42 reports)
- [JASC 2922](https://openairdocs.org/jasc/2922): Hydraulic Filter, Auxiliary (20 reports)
- [JASC 2923](https://openairdocs.org/jasc/2923): Hydraulic Pump, Auxiliary (138 reports)
- [JASC 2925](https://openairdocs.org/jasc/2925): Hydraulic Pressure Relief, Auxiliary (4 reports)
- [JASC 2926](https://openairdocs.org/jasc/2926): Hydraulic Reservoir, Auxiliary (14 reports)
- [JASC 2927](https://openairdocs.org/jasc/2927): Hydraulic Pressure Regulator, Auxiliary (8 reports)
- [JASC 2930](https://openairdocs.org/jasc/2930): Hydraulic Indicating System (549 reports)
- [JASC 2931](https://openairdocs.org/jasc/2931): Hydraulic Pressure Indicator (160 reports)
- [JASC 2932](https://openairdocs.org/jasc/2932): Hydraulic Pressure Sensor (290 reports)
- [JASC 2933](https://openairdocs.org/jasc/2933): Hydraulic Quantity Indicator (121 reports)
- [JASC 2934](https://openairdocs.org/jasc/2934): Hydraulic Quantity Sensor (96 reports)
- [JASC 2997](https://openairdocs.org/jasc/2997): Hydraulic Power System Wiring (343 reports)

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