# JASC 3412: Outside Air Temperature Indicator/Sensor

- Type: JASC system/component code (FAA)
- ATA chapter: 34 Navigation
- Title in the code table: OUTSIDE AIR TEMP. IND./SENSOR
- Service difficulty reports: 254
- FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=37
- Page: https://openairdocs.org/jasc/3412

## What it covers

The unit mounted in the engine induction air intake to sense and transmit temperature to the cockpit indicator. Also for the sensors and instruments which measure and indicate the temperature of ambient air outside the aircraft. Includes associated circuitry and related parts. Typical parts are sensor, indicator, case, etc.

## Service difficulty reports (254, newest 50)

- [SDR CALA2026091519424](https://openairdocs.org/sdr/CALA2026091519424), Sep 13, 2026: Boeing 767322. TAT PROBE. FAULTED. LOSS OF ALL TAT DATA CLIMBING THROUGH 330 LOSS OF AP/AT LNAV/VNA V TCAS/WINDSHEAR TROUBLESHOT IAW SSM 34-12-01-103. FOUN (N671UA)
- [SDR CALA2026082418859](https://openairdocs.org/sdr/CALA2026082418859), Aug 21, 2026: Airbus A320232. ADIRU. FAULTED. REPEAT GRIPE OF IR-1 AFTER TAKEOFF. DEBRIEFED PILOT, AFTER TAKEOFF, IR-1 FAULTED. CAPT FOLLOWED QRH AND SWITCHED TO CAPT (N496UA)
- [SDR SWIA2026051276027](https://openairdocs.org/sdr/SWIA2026051276027), May 12, 2026: Emb ERJ170200LL. TAT PROBE. DEFORMED. SKIN AROUND NR 1 TAT PROBE DEFORMED DUE TO BIRD STRIKE DAMAGE. (FLIGHT 5403) UPON INSPECTION, FOUND THE DEFORMATION ON T (N85374)
- [SDR CALA2026041315316](https://openairdocs.org/sdr/CALA2026041315316), Apr 11, 2026: Boeing 7378. TAT PROBE. FAULTY. PROBE HEAT LIGHT COMES ON TEMP PROBE LIGHT ILLUMINATED IN CRUISE. DIVERTED TO LAX TO AVOID ICING CONDITIONS. REPLACED TA (N47330)
- [SDR CALA2026031614595](https://openairdocs.org/sdr/CALA2026031614595), Mar 12, 2026: Boeing 7379. TAT PROBE. FAULTED. AFTER TAKEOFF WE LOST VNAV AND ALL FUEL TIME AND DISTANCE DATA. A/T THRUST LIMIT BITE CHECK FMC LEFT AND RIGHT OPS CK OK (N37507)
- [SDR AALA202602039460](https://openairdocs.org/sdr/AALA202602039460), Jan 31, 2026: Boeing 7378. TAT PROBE. OVERHEATED. AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS NOT DECLARED DUE TO: DURING CRUISE AT 360 TEMPERATURE PROBE LIGHT ILLUMINATED. A (N323RM)
- [SDR SWAA2025101323837](https://openairdocs.org/sdr/SWAA2025101323837), Oct 11, 2025: Boeing 7377BD. TAT PROBE. OUT OF TOLERANCE. IAS DISAGREE ON TAKEOFF. R+R TOTAL AIR TEMPERATURE PROBE PER MM 34-21-06. (N7715E)
- [SDR ABXA20251007258](https://openairdocs.org/sdr/ABXA20251007258), Oct 7, 2025: Boeing 767381. PROBE. DEFECTIVE. DURING CLIME OUT, TAT PROBE EICAS MESSAGE APPEARED. AC RETURNED TO SJU (ATB) AND LANDED ,MTX GROUNDED AC AND TROUBLESHOT (N390CM)
- [SDR 2025F00220](https://openairdocs.org/sdr/2025F00220), Sep 11, 2025: Airbus A320214. GYRO. FAULTED. NAV ADR 1 FAULT ON ECAM DURING TAKE OFF (REJECTED TAKE OFF) AT SPEED OF 90 KTS (N728AV)
- [SDR AALA202509082697](https://openairdocs.org/sdr/AALA202509082697), Sep 7, 2025: Boeing 737823. TAT PROBE. FAULTED. AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED INROUTE TO LGA DUE TO THE FLIGHT CREW REPORTING THAT AFTER LEVEL, AIRCR (N891NN)
- [SDR HNAA2025081100537](https://openairdocs.org/sdr/HNAA2025081100537), Aug 10, 2025: Emb EMB145LR. RELAY. FAILED. ON TAKE OFF ROLL TAT 2 HEAT INOP, E1-2 IDLE STOP FAIL AND NO TAKE OFF CONFIG MSGS DISPLAYED ON EICAS. NO AURAL MSG DENOT (N641AE)
- [SDR ASMF2025072300517](https://openairdocs.org/sdr/ASMF2025072300517), Jul 23, 2025: Boeing 7378. PROBE. FAULTED. REJECTED TAKE OFF DUE TO AIRSPEED UNRELIABILITY / MASTER CAUTION"EEC ENGINE 1" / TAT PROBE REPLACED
- [SDR CALA2025032103068](https://openairdocs.org/sdr/CALA2025032103068), Mar 19, 2025: Boeing 7378. PROBE. FAULTED. LEFT TEMP PROBE LIGHT ILLUMINATED. MEL 3031D TAT PROBE HEATER INOP. . R&R TEMP PROBE PER AMM TASK 34-21-06 AND ALL OPS C (N17321)
- [SDR CALA2025030702645](https://openairdocs.org/sdr/CALA2025030702645), Mar 5, 2025: Boeing 767322. TAT PROBE. FAULTED. TAT PROBE AUTOTHROT DISC COMPLIED WITH QRH REM/REPL TAT PROBE SENSOR IAW B767-3 AMM 34-12-02-404-008. TAT PROBE TESTS GO (N648UA)
- [SDR HNAA2025021900088](https://openairdocs.org/sdr/HNAA2025021900088), Feb 17, 2025: Emb EMB145LR. SENSOR. FAULTED. TAT 1 HT INOP MSG DISPLAYED AFTER TAKEOFF EXTINGUISHED AFTER LANDING. FACT 18FEB25 06:55 PHL T/S USIING FIM TASK 30-33-0 (N905JH)
- [SDR CALA2025012902102](https://openairdocs.org/sdr/CALA2025012902102), Jan 27, 2025: Boeing 767424ER. TAT PROBE. FAULTY. RIGHT TAT PROBE EICAS MSG ITEM UPDATED IN ORDER TO FLAG SDR. AC RETURN TO GIG AS AN AIR RETURN ON AN EMERGENCY CONDITION (N78060)
- [SDR CALA2025012900223](https://openairdocs.org/sdr/CALA2025012900223), Jan 27, 2025: Boeing 767424ER. TAT PROBE. MALFUNCTIONED. R TAT PROBE EICAS MSG ITEM UPDATED IN ORDER TO FLAG SDR. AC RETURN TO GIG AS AN AIR R TAT PROBE WITH ASSOCIATED R TAT FA (N78060)
- [SDR DALA2025012100502](https://openairdocs.org/sdr/DALA2025012100502), Jan 17, 2025: Boeing 757251. RELAY. FAULTED. SHIP 5656 -DIV/DE- TO ATL DUE TO TAT PROBE MESSAGE. CORRECTIVE ACTION: REPLACED TAT PROBE CURRENT SENSE RELAY K410. (N556NW)
- [SDR ABXA20241011186](https://openairdocs.org/sdr/ABXA20241011186), Oct 11, 2024: Boeing 767306. TAT PROBE. FAILED. CREW REPORTED EICAS MSG "TAT PROBE" INFO: NO A/T, NO L NAV, NO V NAV DURING CLIMB STAGE AND PERFORMED AN AIR TURNBACK. M (N1229A)
- [SDR CALA2024100400751](https://openairdocs.org/sdr/CALA2024100400751), Oct 2, 2024: Boeing 7378. PROBE. FAULTED. TAT AT 99 LOST LNAV/VNAV AT T/O LOST N1 LIMITS AND ENG 1/2 AIR DATA REPLACED TAT PROBE REF AMM TASK 34-21-06-000-801, OP (N27273)
- [SDR CALA2024070501965](https://openairdocs.org/sdr/CALA2024070501965), Jun 30, 2024: Boeing 757224. HOSE. LEAKING. FO ALTIMETER SPLIT FROM CAPTAIN. CAPTAIN SIDE IS CORRECT LOCKED UNLOCKED. PERFORMED FULL RANGE PITOT-STATIC LEAK CHECK & (N48127)
- [SDR AALA202405298176](https://openairdocs.org/sdr/AALA202405298176), May 28, 2024: Boeing 737823. TAT PROBE. FAILED. AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: ON CLIMB MULTIPLE FAILURE WITH AUTO THROTTLE, TEMP CONTROL, AND (N826NN)
- [SDR DALA2024031103195](https://openairdocs.org/sdr/DALA2024031103195), Mar 8, 2024: Airbus A319114. TAT PROBE. DAMAGED. SHIP 3127 DURING LIGHTING STRIKE INSPECTION FOUND LT TAT PROBE DAMAGED. CORRECTIVE ACTION: R&R LT TAT PROBE PER A319 AMM (N327NB)
- [SDR IPXA2023121901449](https://openairdocs.org/sdr/IPXA2023121901449), Dec 19, 2023: Boeing 75724APF. UNKNOWN. UNKNOWN. *** DIVERSION *** AT APPROX V/R CAPT PFD DISPLAYED WINDSHEAR WITH FULL SCALE A/S AND ALT DEVIATIONS OVERSPEED, RUDDER RA (N427UP)
- [SDR AALA202306163183](https://openairdocs.org/sdr/AALA202306163183), Jun 13, 2023: Boeing 737823. TAT PROBE. FAULTY. AIRCRAFT WAS GROUNDED: ON TAKEOFF LOST N1 REFERENCE READ OUT ON DISPLAYS, LOST FIRST OFFICERÏ¿½S FLIGHT DIRECTOR, AND AU (N916AN)
- [SDR IPXA2023011990061](https://openairdocs.org/sdr/IPXA2023011990061), Jan 19, 2023: Boeing 75724APF. SENSOR. FAULTED. ATB, EMERGENCY DECLARED, TAT PROB EICAS AT 400 FT AGL. REMOVED AND REPLACED TAT PROBE, OPS CHECK GOOD IAW AMM 34-12-02. (N474UP)
- [SDR 2023F00000](https://openairdocs.org/sdr/2023F00000), Dec 9, 2022: Boeing 7377Q8. PROBE. FAULTED. A/T LIM MSG ON UPPER DU (NO VNAV AVAILABLE, NO A/T AVAILABLE) BITE MSG 73-31-711 BITE MSG 73-11-282 (MOT 1) TAT FAIL PRO
- [SDR AALA202207190706](https://openairdocs.org/sdr/AALA202207190706), Jul 15, 2022: Airbus A319132. TAT PROBE. DEFECTIVE. AIRCRAFT WAS GROUNDED: DURING TAKE OFF ROLL AT DFW BOTH ENGINES WERE EXTREMELY SLOW TO ACCELERATE. AUTO BRAKES DIDN'T AC (N822AW)
- [SDR AALA202207197413](https://openairdocs.org/sdr/AALA202207197413), Jul 15, 2022: Airbus A319132. TAT PROBE. DEFECTIVE. AIRCRAFT WAS GROUNDED: DURING TAKE OFF ROLL AT DFW BOTH ENGINES WERE EXTREMELY SLOW TO ACCELERATE. AUTO BRAKES DIDN'T AC (N822AW)
- [SDR IPXA2022061783207](https://openairdocs.org/sdr/IPXA2022061783207), Jun 17, 2022: Boeing 75724APF. AVIONICS UNIT. INOPERATIVE. INSPECTION TYPE:N/A**ATB** - ON CLIMB OUT ABOVE 10,000 FEET THE AIRSPEED TAPE VMO/MMO (CHECKERED TAPE) WOULD NOT GO ABOV (N470UP)
- [SDR QXEA2022041800158](https://openairdocs.org/sdr/QXEA2022041800158), Apr 17, 2022: Bombdr DHC8402. EICAS. FAULT MESSAGE. STANDBY ISI INSTRUMENT AIRSPEED AND ALTITUDE WAS FLUCTUATING IN FLIGHT AND ON THE GROUND. CREW NOTICED AIRSPEED 280 KTS  (N403QX)
- [SDR CALA2022041400983](https://openairdocs.org/sdr/CALA2022041400983), Apr 14, 2022: Airbus A319131. SENSOR. FAILED. ADR 1 FAULT ON CLIMBOUT REPLACED #1 ADR REF AMM 34-12-34-400-001, GROUND CHECKS OK. ADD EMP:U303859 ROTABLE PARTS CHANGE (N852UA)
- [SDR UIEA2022032600242](https://openairdocs.org/sdr/UIEA2022032600242), Mar 26, 2022: Boeing 74747UF. AOA. FAILED. CREW REPORTED AUTOPILOT FAILURES, SINGLE IRU MODE, MULTIPLE ADC ISSUES, WHICH WERE CONFIRMED IN AHM.(<P ><SPAN>REPLACED  (N492MC)
- [SDR AALA202112103496](https://openairdocs.org/sdr/AALA202112103496), Dec 2, 2021: Boeing 737*. TAT PROBE. FAULTY. AIRCRAFT WAS NOT GROUNDED: ICING ISSUE WITH PROBE HEATER ON MEL, FLIGHT RETURNED TO FIELD. **SUPPLEMENTAL REPORT: REPLAC (N957AN)
- [SDR CALA2021092001607](https://openairdocs.org/sdr/CALA2021092001607), Sep 19, 2021: Boeing 767322. TAT PROBE. FAULTED. TAT AND SAT INDICATING 20 C HIGH REPLACED TAT PROBE PER MM 34-12-02. TEST OK. ACCOMPLISHED TEST 4 REF MM 71-00-00. ALL I (N675UA)
- [SDR DALA2021090105158](https://openairdocs.org/sdr/DALA2021090105158), Aug 28, 2021: Boeing 767324. PROBE. FAILED. SHIP 1521 EXCESSIVE WHITE PUFFS MIST/SMOKE FROM CAPTAINS SIDE PITOT TUBES OR TAT ON TAXI INTERMITTENT. CORRECTIVE ACTION (N394DL)
- [SDR 2HGR2021061201](https://openairdocs.org/sdr/2HGR2021061201), Jun 10, 2021: Cndair CL6002B16. WARNING MESSAGE. FALSE INDICATION. ON POST TAXI AT KLAX, CREW NOTICED DADC DATA INVALID FAULT MESSAGE, CREW NOTICED THE SAT & TAT WERE 98 DEGREES CELSIUS.  (N825SG)
- [SDR FDEA202105191311](https://openairdocs.org/sdr/FDEA202105191311), May 19, 2021: Boeing 757232. PROBE. FAILED. PDIS 990 30-30 7688 19MAY21 MEM FACT U LOGPAGES:2903863 TAT PROBE AND ASSOCIATED EICAS MSG ON CLIMB OUT, EMERGENCY DECLA (N990FD)
- [SDR HNAA2021050300164](https://openairdocs.org/sdr/HNAA2021050300164), Apr 30, 2021: Emb EMB145LR. TAT PROBE. MALFUNCTIONED. IN CRUISE TAT 2 INOPERATIVE IN EICAS. NO NOTED INDICATION ISSUES. R & R TAT 2 SENSOR IAW AMM 34 15 03. OPS CHECKED GOOD. (N600BP)
- [SDR AALA202104099014](https://openairdocs.org/sdr/AALA202104099014), Apr 8, 2021: Airbus A321211. SENSOR. INOPERATIVE. AIRCRAFT WAS GROUNDED: ON DECENT THRUST SHOULD HAVE BEEN IDLE, BUT FULLY AUTHORITY DIGITAL ELECTRONIC CONTROLLER SEEMS T (N150UW)
- [SDR AALA202104099005](https://openairdocs.org/sdr/AALA202104099005), Apr 8, 2021: Airbus A321211. SENSOR. INOPERATIVE. AIRCRAFT WAS GROUNDED: ON DECENT THRUST SHOULD HAVE BEEN IDLE, BUT FULLY AUTHORITY DIGITAL ELECTRONIC CONTROLLER SEEMS T (N150UW)
- [SDR CALA2021040500420](https://openairdocs.org/sdr/CALA2021040500420), Apr 5, 2021: Boeing 767322. TAT PROBE. FAULTED. TAT PROBE MESSAGE ON LIFTOFF FOUND CB P63 GRID L 18 "L TAT" PROBE HEAT OPEN. CLOSED CB AND PERFORMED OPS CK REF AMM 34-1 (N673UA)
- [SDR QXEA2021022500079](https://openairdocs.org/sdr/QXEA2021022500079), Feb 24, 2021: Bombdr DHC8402. WIRE SPLICE. DAMAGED. STBY PITOT HEAT CAUTION LIGHT ILLUMINATED DURING CRUISE. WHILE COMPLETING THE CHECKLIST IT EXTINGUISHED AGAIN. REMOVED F (N452QX)
- [SDR CALA2021010600014](https://openairdocs.org/sdr/CALA2021010600014), Jan 6, 2021: Airbus A320232. SENSOR. MALFUNCTIONED. LOSS OF ADR 1 AND 3 / .ADR 1 REPLACED TAT SENSOR 11FP1, REF TASK 34-11-18-000-001-A. OPERATIONS CHECK PASS. S/N OFF 0892 (N405UA)
- [SDR AALA202008259007](https://openairdocs.org/sdr/AALA202008259007), Aug 24, 2020: Boeing 737823. TAT PROBE. INOPERATIVE. AIRCRAFT WAS GROUNDED: ALTITUDE AND AIRSPEED DISAGREE MESSAGES AT FL380, BOTH SELF-CORRECTED ON DESCENT. REPLACED TOTAL  (N806NN)
- [SDR YENA2020062800381](https://openairdocs.org/sdr/YENA2020062800381), Jun 25, 2020: Airbus A320232. SENSOR. FAILED. FLT 647, RETURNED TO FIELD. ON CLIMB OUT, AP 1 ENGAGED FL 280, ACFT PITCHED DOWN, SAT & TAT SHOWED EXTREME NEG NUMBERS.  (N589JB)
- [SDR CALA2020032700735](https://openairdocs.org/sdr/CALA2020032700735), Mar 27, 2020: Boeing 737924ER. PROBE. DEFECTIVE. LOST ALL TEMP AND PERFORMANCE DATA ON CLIMBOUT R&AMP;R TAT PROBE REF AMM 34-21-06.OPS CHECK NORMAL.PERFORMED LAND V ERY  (N39450)
- [SDR ASAA2020012832026](https://openairdocs.org/sdr/ASAA2020012832026), Jan 28, 2020: Boeing 737890. PROBE. FAULTED. ABOUT 45 MIN INTO FLIGHT, A/T LIM ANNUNCIATED AND VNAV DISCONNECTED. REF PREVIOUS WRITE-UPS ON LOG PAGE 12089346 AND 120 (N530AS)
- [SDR HNAA2020012700029](https://openairdocs.org/sdr/HNAA2020012700029), Jan 26, 2020: Emb EMB145LR. PROBE. FAILED. ON T/O TAT1 INOP W/ NO CONFIG MSG. C/W FIM 30-33-00-810-801A. MSG CLEARED AND D/N RETURN. TAT 1 INOP ON T/O ASSOCIATED W (N620AE)
- [SDR DALA2020011500316](https://openairdocs.org/sdr/DALA2020011500316), Jan 12, 2020: Boeing 737932ER. PROBE. FAILED. SHIP 3861 -DIV- TO MCO DUE BOTH AUTOPILOTS DISCONNECTED, NO AUTO THROTTLE AND TAT PROBE MESSAGE. CORRECTIVE ACTION: PERF (N861DN)

All 254: https://openairdocs.org/jasc/3412/reports.md

## Other codes in chapter 34

- [JASC 3400](https://openairdocs.org/jasc/3400): Navigation System (692 reports)
- [JASC 3410](https://openairdocs.org/jasc/3410): Flight Environment Data (218 reports)
- [JASC 3411](https://openairdocs.org/jasc/3411): Pitot/Static System (1,586 reports)
- [JASC 3413](https://openairdocs.org/jasc/3413): Rate of Climb Indicator (157 reports)
- [JASC 3414](https://openairdocs.org/jasc/3414): Airspeed/Mach Indicator (860 reports)
- [JASC 3415](https://openairdocs.org/jasc/3415): High Speed Warning (39 reports)
- [JASC 3416](https://openairdocs.org/jasc/3416): Altimeter, Barometric/Encoder (1,256 reports)
- [JASC 3417](https://openairdocs.org/jasc/3417): Air Data Computer (1,210 reports)
- [JASC 3418](https://openairdocs.org/jasc/3418): Stall Warning System (1,641 reports)
- [JASC 3420](https://openairdocs.org/jasc/3420): Attitude and Direction Data System (772 reports)
- [JASC 3421](https://openairdocs.org/jasc/3421): Attitude Gyro and Indicating System (1,142 reports)
- [JASC 3422](https://openairdocs.org/jasc/3422): Directional Gyro and Indicating System (649 reports)
- [JASC 3423](https://openairdocs.org/jasc/3423): Magnetic Compass (101 reports)
- [JASC 3424](https://openairdocs.org/jasc/3424): Turn and Bank/Rate of Turn Indicator (153 reports)
- [JASC 3425](https://openairdocs.org/jasc/3425): Integrated Flight System (1,150 reports)
- [JASC 3430](https://openairdocs.org/jasc/3430): Landing and Taxi Aids (56 reports)
- [JASC 3431](https://openairdocs.org/jasc/3431): Localizer/VOR System (129 reports)
- [JASC 3432](https://openairdocs.org/jasc/3432): Glide Slope System (66 reports)
- [JASC 3433](https://openairdocs.org/jasc/3433): Microwave Landing System (26 reports)
- [JASC 3434](https://openairdocs.org/jasc/3434): Marker Beacon System (27 reports)
- [JASC 3435](https://openairdocs.org/jasc/3435): Heads Up Display System (10 reports)
- [JASC 3436](https://openairdocs.org/jasc/3436): Wind Shear Detection System (70 reports)
- [JASC 3440](https://openairdocs.org/jasc/3440): Independent Position Determining System (261 reports)
- [JASC 3441](https://openairdocs.org/jasc/3441): Inertial Guidance System (289 reports)
- [JASC 3442](https://openairdocs.org/jasc/3442): Weather Radar System (3,442 reports)
- [JASC 3443](https://openairdocs.org/jasc/3443): Doppler System (110 reports)
- [JASC 3444](https://openairdocs.org/jasc/3444): Ground Proximity System (552 reports)
- [JASC 3445](https://openairdocs.org/jasc/3445): Air Collision Avoidance System (214 reports)
- [JASC 3446](https://openairdocs.org/jasc/3446): Non Radar Weather System (23 reports)
- [JASC 3450](https://openairdocs.org/jasc/3450): Dependent Position Determining System (106 reports)
- [JASC 3451](https://openairdocs.org/jasc/3451): DME/TACAN System (197 reports)
- [JASC 3452](https://openairdocs.org/jasc/3452): ATC Transponder System (624 reports)
- [JASC 3453](https://openairdocs.org/jasc/3453): Long-Range Navigation (LORAN) System (175 reports)
- [JASC 3454](https://openairdocs.org/jasc/3454): Visual Omnirange (VOR) System (317 reports)
- [JASC 3455](https://openairdocs.org/jasc/3455): Automatic Direction Finder (ADF) System (164 reports)
- [JASC 3456](https://openairdocs.org/jasc/3456): Omega Navigation System (9 reports)
- [JASC 3457](https://openairdocs.org/jasc/3457): Global Positioning System (635 reports)
- [JASC 3460](https://openairdocs.org/jasc/3460): Flight Management Computing Hardware System (4,690 reports)
- [JASC 3461](https://openairdocs.org/jasc/3461): Flight Management Computing Software System (68 reports)
- [JASC 3497](https://openairdocs.org/jasc/3497): Navigation System Wiring (269 reports)

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