OBD LensChrysler: P1336
Crankshaft / Camshaft Sensor Range / Performance
Krank Mili / Eksantrik Mili Sensörü Aralığı / Performansı
- Reference namespace
- chrysler
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Chrysler.
5 profiles assigned this reference family
- OBD-II / EOBDChrysler
- 5.7L / 6.4L Hemi EngineChrysler
- Grand Voyager 2009Chrysler · 2009–2009
- OBD-II / EOBD + CAN and ATChrysler
- Pacifica Minivan 2015+Chrysler · 2015–onward
Dodge / Fiat: P1336
Torque control(request)
- Reference namespace
- fiat
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Fiat, Dodge.
27 profiles assigned this reference family
- 500Fiat
- 500 1.2 Fire 8V (CAN)Fiat
- 500 1.3 MultiJet 16V (CAN)Fiat
- 500 1.4 MultiAir 16V (CAN)Fiat
- 500 1.4 T-Jet 16V (CAN)Fiat
- 500e (2013 - 2019)Fiat · 2013–2019
- 500e (2020-) BEV ElectricFiat · 2020–onward
- 500XFiat
- Bravo 1.4 T-Jet 16V (CAN)Fiat
- Bravo 1.4 T-Jet 16V (KWP)Fiat
- Dart / ViaggioDodge
- Doblo 1.3 MultiJet 16V (CAN)Fiat
- Doblo 1.4 8v KWPFiat
- Freemont DieselFiat
- Multijet 2.0 Diesel + ZF 9HP48Fiat
- Punto 1.2 8V (CAN)Fiat
- Punto 1.3 MultiJet 16V (CAN)Fiat
- Punto 1.4 Fire 8V (CAN)Fiat
- Punto 1.4 MultiAir 16V (CAN)Fiat
- Punto 1.4 T-Jet 16V (CAN)Fiat
- Punto 1.4 T-Jet 16V (KWP)Fiat
- Qubo 1.2 Fire 8V (CAN)Fiat
- Qubo 1.3 MultiJet 16V (CAN)Fiat
- Tipo / Egea 1.6 MultijetFiat
3 more related profiles are listed in the vehicle directory.
Ford: P1336
Crank / Cam Sensor Range / Performance
- Reference namespace
- ford
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Ford.
28 profiles assigned this reference family
- 3.0L & 3.2L DieselFord
- Bronco 2021-Ford · 2021–onward
- EcoSport 1.6 Ztec 2009-Ford · 2009–onward
- Everest Gen.3 U704/UB (2022-n.d.) 3.0 Diesel + 10ATFord · 2022–onward
- Explorer 3.5 TiVCTFord
- Explorer Gen.6 3.0L (2020-n.d.)Ford · 2020–onward
- F150 VCTFord
- Falcon 4.0Ford · 2011–2014
- Focus II ST 2.5Ford
- Ford PHEV plug-in hybridFord
- Fusion 2.0 ecoboostFord
- Maverick 2022-n.d. 2.5 HybridFord · 2022–onward
- Mondeo Hybrid / Fusion HybridFord
- Mustang 2.3 EcoBoost (2015-2018)Ford · 2015–2018
- Mustang 2011 5.0 V8Ford · 2011–2011
- Mustang 2011-2017 3.7 V6Ford · 2011–2017
- Mustang GT 2016 5.0Ford · 2016–2016
- Mustang Mach-E (2023-)Ford · 2023–onward
- Mustang Mach-E / F-150 Lightning / E-TransitFord
- OBD-II / EOBD + CAN and extra PIDsFord
- OBDII/EOBD + SAE J1850 (Old Ford vehicles and trucks)Ford · 2004–2004
- Powerstroke 6.0L CANFord
- Powerstroke 6.4L CANFord
- Powerstroke 6.7L CANFord
4 more related profiles are listed in the vehicle directory.
GM: P1336
Crankshaft Position (CKP) System Variation Not Learned
- Reference namespace
- gm
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Euler / Great Wall / Harvard / Haval: P1336
Crankshaft Position Sensor (CKP) Signal Adaptation Not Performed
Не проведена адаптация сигнала от датчика положения коленчатого вала (ДПКВ)
- Reference namespace
- haval
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Great Wall, Euler, Haval, Harvard.
34 profiles assigned this reference family
- OBD-II / EOBDEuler
- Cannon/Poer/Sahar (2023-) 2.0 DieselGreat Wall · 2023–onward
- Cannon/Poer/Sahar (2023-) 2.4 DieselGreat Wall · 2023–onward
- Cool Dog / H3 (2022-n.d.)Great Wall · 2022–onward
- Dagou / Dargo / Big Dog / 大狗Great Wall
- F7 (2020-), F7x (4B15A, 4C20B, 4G15K)Haval · 2020–onward
- F7 (2020-), F7x (4C20NT)Haval · 2020–onward
- First Love / Jolion 1.5T (4B15D)Harvard
- First Love / Jolion 1.5T (4G15H, 4G15K, 4B15C)Harvard
- Good Cat / Funky Cat / ES11 / Haomao / Ora 03 / Lightning Cat / ORA 07 / 好猫Euler
- H2 (2019-2021)Haval · 2019–2021
- H5 4D20 (Bosch)Great Wall
- H5 4D20 (Delphi)Great Wall
- H5 4G63TGreat Wall
- H5 Gen.2 (2023-) 4C20BGreat Wall · 2023–onward
- H5 Gen.2 (2023-) 4D20MGreat Wall · 2023–onward
- H6 gen.2 (2017-2020) / H6 Coupe (2017-2021) / H6 Sport 1.5T + 6ATHaval · 2017–2021
- H6 gen.3 (2020-)Haval · 2020–onward
- H6 Gen.3 HEV/PHEV (2021-)Haval · 2021–onward
- H7 (2025-) / F7 (2025-) / Shenshou (2025-)Great Wall · 2025–onward
- H9 2.0 2014-2019Haval · 2014–2019
- H9 2020-2024 (4B15A, 4C20B)Haval · 2020–2024
- H9 2020-2024 (4D20M)Haval · 2020–2024
- H9 New 2024- (2.0 Gasoline 4C20B)Haval · 2024–2024
10 more related profiles are listed in the vehicle directory.
Acura / Honda: P1336
Engine Speed (RPM) Fluctuation Sensor Intermittent Interruption
- Reference namespace
- honda
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Honda, Acura.
12 profiles assigned this reference family
- Accord, Civic, CRV, CX-7 etc. 2008-2012 (var.1)Honda · 2008–2012
- Accord, Civic, CRV, CX-7 etc. 2008-2012 (var.2)Honda · 2008–2012
- Clarity PHEV, e:NY1Honda
- CR-V RE6, Accord DieselHonda
- EHonda
- Fit GK3Honda
- Honda/Acura HybridsAcura
- Insight II (2010-2014)Honda · 2010–2014
- OBD-II / EOBD + AT/CVT (CAN)Acura
- OBDII / EOBD GM based Ultium EV vehicles (2021-2025)Acura · 2021–2025
- OBDII / EOBD GM based Ultium EV vehicles (2026-n.d.)Acura · 2026–onward
- WWH-OBD (CAN 29 bit)Honda · 2026–2026
Genesis / Hyundai / Kia: P1336
#6 MF Signal Line Short; Crankshaft / Camshaft Sensor Range / Performance
- Reference namespace
- hyundai-kia
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Kia, Genesis, Hyundai.
401 profiles assigned this reference family
- OBD-II / EOBDHyundai
- OBD-II / EOBDGenesis
- Accent III / Verna MC 1.5 CRDI DieselHyundai
- Accent III MC / Verna 1.4/1.6 MPIHyundai
- Accent IV (RB/RC) / Verna / i25 / Excel III / Grand Pony 2010-2017 1.4/1.6 MPIHyundai · 2010–2017
- Accent IV RB 1.4/1.6 GDIHyundai
- Accent IV RB 1.6 CRDIHyundai
- Accent V / Verna HC 1.5 CRDI DieselHyundai
- Accent V / Verna HC 1.6 CRDI Diesel (2018-2022)Hyundai · 2018–2022
- Cadenza VG / K7 (2010-2016) 2.4 GDIKia · 2010–2016
- Cadenza VG / K7 (2011-2016) 2.7Kia · 2011–2016
- Cadenza VG / K7 (2011-2018) 3.0Kia · 2011–2018
- Cadenza VG / K7 (2011-2018) 3.0 LPIKia · 2011–2018
- Carens KY 1.5 CRDI Diesel (2021-n.d.)Kia · 2021–onward
- Carens/Rondo 2 UN (2006-2012) 2.0/2.4 MPI CANKia · 2006–2012
- Carens/Rondo 3 RP (2012-2021)Kia · 2012–2021
- Carens/Rondo 3 RP (2012-2021) 1.6 GDIKia · 2012–2021
- Carens/Rondo 3 RP (2013-2014) 1.7 CRDI Diesel TCIKia · 2013–2014
- Carens/Rondo 3 RP (2015-2021) 1.7 CRDI Diesel TCI-U2Kia · 2015–2021
- Carnival KA4 1.6 T-GDI HEV (2020-)Kia · 2020–onward
- Carnival KA4 2.2 CRDI Diesel (2020-)Kia · 2020–onward
- Carnival KA4 PE 2.0 T-GDI (2020-)Kia · 2020–onward
- Carnival KA4 PE 3.5 (2020-)Kia · 2020–onward
- Carnival/Sedona VQ-2 2.7 V6 (2006-2014)Kia · 2006–2014
377 more related profiles are listed in the vehicle directory.
Jaguar / Land Rover: P1336
Crankshaft/Camshaft Sensor Range/Performance
- Reference namespace
- jaguar-land-rover
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Land Rover, Jaguar.
42 profiles assigned this reference family
- Defender 2007-2010 2.4LLand Rover · 2007–2010
- Defender Puma 2.2L DieselLand Rover
- Discovery 4 2.7L [EN]Land Rover
- Discovery 4 2.7L [RU]Land Rover
- Discovery 4 3.0L OBD-II + Extra / RangeRover 2009-2012 5.0LLand Rover · 2009–2012
- Discovery 5 3.0 Diesel (2021-n.d.)Land Rover · 2021–onward
- Discovery III 2.7L TD6 [EN]Land Rover
- Discovery III 2.7L TD6 [RU]Land Rover
- Discovery III 4.4 V8Land Rover
- Discovery Sport 2015-2016 2.2DLand Rover · 2015–2016
- Discovery Sport 2017-2020Land Rover · 2017–2020
- Evoque Gen.1 2012-2017 Diesel 2.0/2.2Land Rover · 2012–2017
- Evoque Gen.1 2012-2017 Gasoline 2.0Land Rover · 2012–2017
- F-Pace 2017 3.0 V6 DieselJaguar · 2017–2017
- F-Pace 3.0 Gasoline (Supercharged) (2016-2017)Jaguar · 2016–2017
- Freelander II 2.2L [EN]Land Rover
- Freelander II 2.2L [RU]Land Rover
- Freelander II 3.2LLand Rover
- F-Type 3.0 Superchared PS306 (2018-)Jaguar · 2018–onward
- Ingenium 2.0 Diesel (AJ200D, 204DTA, 204DTD)Jaguar
- Ingenium 2.0 Gasoline (AJ200P, PT204)Jaguar
- I-PaceJaguar
- OBD-II / EOBD + extra (CAN)Jaguar · 2002–2014
- PT306/AJ20P6 3.0LJaguar
18 more related profiles are listed in the vehicle directory.
Dodge / Mitsubishi: P1336
Crank / Cam Sensor Range / Performance; Piston position sensor 2
- Reference namespace
- mitsubishi
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Mitsubishi, Dodge.
31 profiles assigned this reference family
- ASX 2.2 ATMitsubishi
- Colt 1.3/1.5Mitsubishi
- Eclipse Cross 1.5T/2.0/2.4 + CVTMitsubishi
- Eclipse Cross 2.2 Diesel / Delica D5 (2019-) + 8ATMitsubishi · 2019–onward
- Eclipse Cross PHEVMitsubishi
- Galant 9 AT CANMitsubishi
- i-MiEVMitsubishi
- L200 / Triton Gen.6 (LC/MV) (2023-n.d.) 4N16Mitsubishi · 2023–onward
- L200 2.5 DI-DMitsubishi
- Lancer VIII 1.5/1.6 ATMitsubishi
- Lancer VIII 2.0/2.4 CVTMitsubishi
- Lancer VIII 2.0/2.4 SSTMitsubishi
- Mirage (2012-), Space Star, Dodge Attitude 1.2Dodge · 2012–onward
- OBD-II / EOBD + MUT-2 (K-LINE) (-2005)Mitsubishi · 2005–2005
- Outlander II 2.2 DI-DMitsubishi
- Outlander II, III 2.3 DI-DMitsubishi
- Outlander II, XL, III (3.0+AT)Mitsubishi
- Outlander IV 1.5T 4B40 (2022-)Mitsubishi · 2022–onward
- Outlander IV 2.5 PR25DD (2021-)Mitsubishi · 2021–onward
- Outlander PHEVMitsubishi
- Pajero IV 3.0, 3.8 V6 [EN]Mitsubishi
- Pajero IV 3.0, 3.8 V6 [RU]Mitsubishi
- Pajero IV 3.0, 3.8 V6 + AT V4A51 [EN]Mitsubishi
- Pajero IV 3.0, 3.8 V6 + AT V4A51 [RU]Mitsubishi
7 more related profiles are listed in the vehicle directory.
Infiniti / Nissan: P1336
Crank / Cam Sensor Range / Performance; CKP Sensor (POS) Cog
- Reference namespace
- nissan
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Nissan, Infiniti.
62 profiles assigned this reference family
- 370Z Z34 3.7 V6Nissan
- Almera G15 + ATNissan
- Altima 2013-Nissan · 2013–onward
- Altima L32 2.5Nissan
- Altima L32 3.5 V6Nissan
- Armada TA60 5.6 V8Nissan
- Frontier D40 2.5Nissan
- Frontier D40 4.0 V6Nissan
- Frontier D41 Gen.3 (2022-n.d.)Nissan · 2022–onward
- GT-R (R35)Nissan
- Juke 1.5dci K9K 636 [EN]Nissan
- Juke 1.5dci K9K 636 [RU]Nissan
- Juke 2014-Nissan · 2014–onward
- Juke F15 (2010-2018) 1.6 TURBO + CVTNissan · 2010–2018
- Kicks HP15 e-Power (Gen.1)Nissan
- Leaf ZE0/AZE0 (2010-2017)Nissan · 2010–2017
- Leaf ZE1 (2017-2025)Nissan · 2017–2025
- March/Micra K13 1.5Nissan
- March/Micra K13 1.6Nissan
- Maxima A35 3.5 V6Nissan
- Murano Z51 3.5 V6 + CVTNissan
- Murano Z52 2015-Nissan · 2015–onward
- Nissan Consult IIInfiniti · 2001–2008
- Nissan Consult II ABS ONLYInfiniti · 2001–2008
38 more related profiles are listed in the vehicle directory.
Generic OBD2: P1336
Crank / Cam Sensor Range / Performance
Не считывается показатель датчика положения коленвала (CKP)
- Reference namespace
- obd2
- Source revision
- legacy-2.2.20
Generic OBD2 definition; confirm the protocol and vehicle-specific service information.
Belgee / Geely / Proton: P1336
Crank / Cam Sensor Range / Performance
- Reference namespace
- proton
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Belgee, Geely, Proton.
5 profiles assigned this reference family
Chevrolet / Citroen / General Motors / Opel / Peugeot: P1336
Crank/Cam sensor range/performance S2000PM1/2 - High misfire on several cylinders ME7.4.5. Combustion misfiring on unspecified cylinders.
- Reference namespace
- stellantis-psa
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Chevrolet, Opel, Citroen, General Motors, Peugeot.
35 profiles assigned this reference family
- OBD-II / EOBDCitroen
- 1.5 BlueHDI ECU MD1CS003Citroen
- 307 (2001-2005)Peugeot · 2001–2005
- 308 (T9) + 6AT (CAN)Peugeot
- 308 (T9) + 8AT (CAN)Peugeot
- 308 + 4AT (CAN)Peugeot
- 308, 508, etc. with 1.6 BOSCH MED 17.4.2Peugeot
- A14NETChevrolet
- A20DTHChevrolet
- AISIN8Citroen
- AL4 K-Line/KWPCitroen
- Astra G Y17DT (1998-2004)Opel · 1998–2004
- B16DTHChevrolet
- B20DTHChevrolet
- Bolt / Ampera-EChevrolet
- Bolt / Ampera-E 2017-2020Chevrolet · 2017–2020
- Bosch MEDV 17.4.4 ECU (EP6FDTX)Citroen
- C4 B7 (2010-)Citroen · 2010–onward
- C4 with 1.6 BOSCH MED 17.4.2Citroen
- Combo C 1.3 CDTiChevrolet · 2001–2011
- ECU EDC16C3 KWPCitroen
- ECU EDC17C10_BR2Citroen
- ECU EDC17C60Citroen
- ECU MD1CS003Citroen
11 more related profiles are listed in the vehicle directory.
УАЗ: P1336
Несовпадение показаний датчиков 1 и 2 положения дроссельной заслонки
- Reference namespace
- uaz
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: УАЗ.
4 profiles assigned this reference family
Audi / Jetta / MAN / Seat / Skoda / Volkswagen: P1336
Crankshaft Position (CKP) System Variation Not Learned; Engine Torque Monitoring Adaptation at limit
Crankshaft Position (CKP) System Variation Not Learned; Engine Torque Monitoring Adaptation at limit
- Reference namespace
- vag
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Skoda, Volkswagen, Audi, Seat, MAN, Jetta.
56 profiles assigned this reference family
- Amarok gen.1 (2010-2022) 2.0 TDIVolkswagen · 2010–2022
- Amarok gen.1 (2010-2022) 3.0 TDIVolkswagen · 2010–2022
- Caravelle 2.5 TDIVolkswagen
- Crafter NF 2016-2019, TGE 1 2.0 TDIMAN · 2016–2019
- EV: e-Golf (24 kWh) 2014-2016Volkswagen · 2014–2016
- EV: e-Golf (36 kWh) 2017-2021Volkswagen · 2017–2021
- EV: eTron 55Audi
- EV: e-UP! gen.2, Citigo E, Mii EV (32kWh)Seat · 2019–onward
- EV: e-Up!, CitiGo E, Mii EV gen.1Jetta
- MLB: 2.0 TSI/TFSI: CAEB, CDNC var.1Audi
- MLB: 2.0 TSI/TFSI: CAEB, CDNC var.2Audi
- MLB: 2.0 TSI/TFSI: CPMAAudi
- MLB: A5/S5 B8/8T (2007-2013) + ATAudi · 2007–2013
- MLB: Diesel DPF var.16 [EA896]Audi
- MLB: Diesel DPF var.6 [EA897]Audi · 2008–2016
- MLB: Diesel var.14 EA189 2.0 TDI (UDS ECM ONLY)Audi
- MLB: EA824 4.0 TFSI (CWUB, CWUC)Audi · 2015–2018
- MLB-EVO: Diesel DPF var.12 [EA897 Evo 3.0TDI] (Audi: A4 8W, A5 8W, Q5 80A, Q7 4M, A8 4N, A7 4K8, A6 4K, Q8 4MN, VW Touareg CR)Audi
- MLB-EVO: Diesel DPF var.13 [EA288 Evo 2.0TDI] (Audi: A4 8W, A5 8W, Q5 80A, Q7 4M, A8 4N, A7 4K8, A6 4K, Q8 4MN, VW Touareg CR)Audi
- MLB-EVO: Diesel DPF var.15 [EA897 Evo3 3.0TDI]Audi
- MLB-EVO: Diesel DPF var.4 [EA288 2.0 TDI] (Audi: A4 8W, A5 8W, Q5 80A, Q7 4M, A8 4N, A7 4K8, A6 4K, Q8 4MN)Audi
- MLB-EVO: Diesel DPF var.5 [EA897 3.0TDI] (Audi: A4 8W, A5 8W, Q5 80A, Q7 4M, A8 4N, A7 4K8, A6 4K, Q8 4MN, VW Touareg CR)Audi
- MLB-EVO: Diesel DPF var.8 [EA897 Evo2 3.0TDI] (Audi: A4 8W, A5 8W, Q5 80A, Q7 4M, A8 4N, A7 4K8, A6 4K, Q8 4MN, VW Touareg CR)Audi
- MLB-EVO: Diesel DPF var.9 [EA897 gen.2 3.0TDI] (Audi: A4 8W, A5 8W, Q5 80A, Q7 4M, A8 4N, A7 4K8, A6 4K, Q8 4MN, VW Touareg CR)Audi
32 more related profiles are listed in the vehicle directory.
Polestar / Volvo: P1336
Engine Torque Monitoring Adaptation at limit
- Reference namespace
- volvo
- Source revision
- legacy-oem-dtc-r2-20260924
Reference family assigned by the production catalog. An entry in this family is not proof of a fault or ECU support on every listed vehicle.
Related catalog brands: Polestar, Volvo.
12 profiles assigned this reference family
- 2014-2018 VEA engine (not SPA)Volvo · 2014–2018
- D2 (1.6)Volvo · 2011–2015
- EX90 (2024 - n.d.)Volvo · 2024–onward
- Platform 2 + CAN 29-bit protocolVolvo · 1998–2016
- Platform 2 + ISO 9141-2 protocolVolvo
- Platform 3 MY2008-Volvo · 2008–onward
- S80-V70 with 2.0D Ford engineVolvo
- SPA (4 cylinders: B4204T*, D4204T*)Volvo · 2014–onward
- SPA/CMA (3 cylinders: B3154T*)Volvo · 2014–onward
- V60 D6 PHEV AWD Diesel Plug-in Hybrid (2012-2017)Volvo · 2012–2017
- Volvo P1 platform 2.0D diesel 2004-2010Volvo · 2004–2010
- XC40 EV/C40 EV E400V2/E400V5/E400V6 2020- / Polestar 2Polestar · 2020–onward
What should I check before using this definition?
Keep the full code, module, status and freeze-frame data. Confirm the vehicle’s make, model, year and current manufacturer service information before choosing a repair. This entry does not identify a failed part by itself.
Organize a scan report or recordingOBD Lens production library legacy-owner-2026-10-09-v81. This is a scoped technical reference, not a scan of your car. A catalog relationship does not certify that every ECU, year or engine returns the same signal or code definition.
Read the reference method