Lo4 ca1117 komatsu codeIt is an excavator komatsu pc360lc-10, 2014. PC200-6 / PC300-6 / PC400-6 / PC200-7 fault code, user code (automatically displayed when there is a fault) : E01, Automatic mode system in HYPER system. Receive a 3% Discount on shipments within Anderson's territory. 2)Remove accessory drive (2). DESCRIPTION:. komatsu pc1250-11 pc1250lc-11 pc1250sp-11 hydraulic excavator shop manual sen06624-07 – pdf download. 0 to 15 yd3. The EO2 code is the notice to the operator that there is an electronic problem in the throttle control circuit. SPN: 627 Incorrect. komatsu d155ax-7 bulldozer service repair manual (sen05653-02) • This shop manual contains the necessary technical information for services performed in a workshop. Some of these methods require the use of special tools designed by Komatsu for the specific purpose. 小松. hi mate, so thank for your post but sorry, the download link is not work. 01 Especificación GSN00116-01 Especificación y datos técnicos GSN00125-01. 2) Loosen the sleeve nut at the base and then remove oil level gauge (3). WA380 -7 SERIAL NUMBERS. While holding the fitting, push body (9) in straight until sliding prevention ring (8) hits contact surface (b) at the hexagonal portion on the male side. The step by step instructions show you how to fault find or complete any repair or overhaul, correctly and efficiently, saving time and. The shop manual is divided into the following chapters for the convenience of. 21, 2022, where it will hang to dry. PC360LC. APPLICABLE MODELS : Komatsu PC170LC-10 Excavator. Nothing. All specifications and tolerances are listed. CA1117 Flight Tracker - Track the real-time flight status of CA 1117 live using the FlightStats Global Flight Tracker. (4) $53. ENGINE. Air China CA1117. Note: Instant digital download only – no printed copy or CD-ROM media. Trip. The PC 170 LC 11’s size is 2. View all specs. . com. Failure code [CA1117] (Partial engine controller data loss. Specifications. And is not to be reproduced, used, or disclosed except in accordance with written authorization. The UMS system allows users to search for unclaimed money held by ASIC on behalf of individuals and organisations. Director, Genome Editing Core. 12V140E-3 Series 7. SPN: 627. 5 reports of Mississippi children affected. 全国約300拠点のサービス体制でダントツのサポートをご提供します. Komatsu D65WX-18 Bulldozer Serial Numbers : 90001 and up TABLE OF CONTENTS : 00 INDEX AND FOREWORD 01 SPECIFICATION 10 STRUCTURE AND FUNCTION 20 STANDARD VALUE TABLE 30 TESTING AND ADJUSTING 40 TROUBLESHOOTING 50 IDSASSEMBLY AND ASSEMBLY 60 MAINTENANCE. 424t PC 490 LC 11 machine. This is a COMPLETE Service Repair Manual for the KOMATSU D155AX-8 BULLDOZER. Komatsu’s roots stretch back more than 100 years ago to a lush forest in Japan that was once home to a copper mine, vital to the surrounding community. WA380-6. コマツのマイクロショベルpc01-1aを買っちゃいました。納入の様子と、機能確認、石いじりや狭いところの通り抜け実験に段差乗り越えと最後は. This complete service repair workshop manual PDF download for the PC240LC-11 Komatsu Hydraulic Excavator (SN: A22001 and up) has easy to read text sections with top quality diagrams, pictures and illustrations. 3)Disassemble the accessory drive according to the following procedure. Komatsu WA270-7 Wheel Loader Shop Manual (80001 and up) – SEN06255-02. コマツ機を知り尽くした経験豊かなプロが商品・部品の購入から点検、修理対応まで徹底し. Popular Flights. The GrabCAD Library offers millions of free CAD designs, CAD files, and 3D models. EOE, a network failure. KOMATSU. Anderson Equipment offers. Crawler Excavators. The manual is designed to be used by mechanics and technicians who are responsible for maintaining and repairing Komatsu equipment. Fiat Kobelco SL55BH Skid Steer Loader Service Repair Manual. About Komatsu Australia Komatsu provides essential equipment, technologies and services to the construction, mining, energy, government, waste and quarry industries. The step by step instructions show you how to fault find or complete any repair or overhaul, correcShop Manual WA320-7 WHEEL LOADER. The step by step instructions show you how to fault find or complete any repair or overhaul, correctly and efficiently, saving time and. The Komatsu PC 170 LC 11 can be grouped in the medium sized machine segment in the crawler excavators category. E02 PC-the EPC system; E03, Swing parking brake system; E10, the engine controller power failure, the engine control drive system circuit malfunction (this engine stall; E11,. Komatsu Pc210lc 10 Hydraulic Excavator Shop Manual - Free download as PDF File (. Read Komatsu WA380-7 Wheel Loader Service Repair Manual SN10001 and up by km0d9isiodok on Issuu and browse thousands of other publications on our p. Browse short-form content that's perfect for a quick read. 989N00, the engine controller to lock warning (mode 3). Condition: AFTERMARKET. Drop-down ceiling TVs. You will surely enjoy browsing through the pages and learning how to repair the different parts. Bucket capacity 0. 「商品情報」では充実の商品ラインナップで、お客さまへの最適なソリューションをご提案します。. Nothing. Machinery & Equipment Appraiser. Hydraulic technical information subscribe to my channel for more information and videos, Also press the bell icon so that you don't miss any updates. This complete service repair workshop manual PDF download for the Komatsu D155AX-8 Bulldozer (SN: 100001 and up) has easy to read text sections with top quality diagrams, pictures and illustrations. Komatsu Logo PNG Komatsu is the brand of a Japanese company, which specializes in the manufacturing of industrial and construction machinery. Please advise, thanks. AA10NX air filter clogging. q Connect negative (-) lead to pin No. Request a quote Find a dealer. Komatsu WA320-8 Wheel Loader Shop Manual SEN06597-10 – PDF DOWNLOAD. Engine controller type select. 1)Remove pulley (1). Komatsu Hydraulic Excavator PC360-10, PC360LC-10 workshop service repair manual includes:Manuals and User Guides for Komatsu PC88MR-10. com. please reupload,About Komatsu Forklifts. Order Parts Any Time 24/7/365. Room: 2134 Online and in Room 2134 of the Legislative Building, 401 S. Shop Manual KOMATSU d65px-17 - Free ebook download as PDF File (. . Electrical. Komatsu has a long history of building top quality, heavy-duty equipment. Scheduled: 20:15. com. 00-36 PC88MR-10. read more. m. 发表回帖. Komatsu WA320-7 Wheel Loader Shop Manual Brands: Komatsu Equipment Type: Wheel Loader Manuals Type: Shop Manual Machine Model: WA320-7 Serial Number: 80001 and up Book Code: SEN06202-00 Language. Available options with innovative integrated advanced automation technology – Intelligent Machine Control. Komatsu PC210 Operation & Maintenance Manual (266 pages) HYDRAULIC EXCAVATOR. Komatsu. pdf), Text File (. . Komatsu Europe announces a major upgrade for wheeled excavators PW148-11, PW158-11 and PW160-11. 1)Remove pulley (1). Ce sys-tème assure automatiquement une Komatsu WA270-7 Wheel Loader Service Repair Manual 80001 SERIAL NUMBERS 80001 and up Index and foreword Specification Structure and function Standard value tables Testing and adjusting Troubleshooting Disassembly and assembly Maintenance standard Appendix Diagrams and drawings Specifications Language: English Format: Platform: Windows and Mac With This Original Factory Workshop Manual The Technician can Find and Solve any problems encountered in the operation of your Komatsu Excavator Models of : PC210LC-10 Excavator [S. B @ the HANS, the hydraulic oil from overheating. --(great bend front end loader, komatsu ca1117, 1973 datsun pickup) This is a cool RC engineering car, fun for and adults. and is not to be reproduced, used, or disclosed except in accordance with written authorization from Komatsu America Corp. H60051 and up. It is the world's first hybrid (electro-hydraulic) powered construction equipment. In the past when the. Purchase your next favourite publicationThe step by step instructions show you how to fault find or complete any repair or overhaul, correctly and efficiently, saving time and avoiding costly mistakes. Some of these techniques require the use of tools specially designed by Komatsu for the specific purpose. 2)Remove accessory drive (2). This Complete Service Repair Workshop Manual PDF Download for the Komatsu WA320-7 Wheel Loader (SN: 80001 and up) has easy to read text sections with top quality diagrams, pictures and illustrations. [1] At the time of its. Connect positive (+) lead and negative (-) lead of tester as. 1. First name *. Professor. TROUBLESHOOTING FAILURE CODE (DISPLAY OF CODE) PC360/390LC-10 40-126 D 12 ★ Turn starting switch to ON position and check that this failure code and failure code [CA2639] are not dis- Fault Code: 1117 PID: S251 SPN: 627 FMI: 2/2 LAMP: None SRT: Power Lost Without Ignition Off - Data Erratic, Intermittent, or Incorrect. and up. The step by step instructions show you how to fault find or complete any repair or overhauSearch for and track the flight status of CA1117 from Beijing to Hohhot: flight arrival and departure times, airport delays and airport information. . CA1117 (Air China) - Live flight status, scheduled flights, flight arrival and departure times, flight tracks and playback, flight route and airport. . 00 Índice y Prólogo GSN00123-05. This material is proprietary to Komatsu America Corp. See Komatsu Hydraulic Excavator for sale on rbauction. Komatsu forklifts are designed with the same heavy equipment expertise that give our customers greater value through lower costs of operation daily. NOTICE Komatsu has Operation & Maintenance Manuals written in some other languages. STEEL DISC. Add to Cart. Seats. The cost to diagnose the C1117 code is 1. Komatsu Pc210lc 10 Hydraulic Excavator Shop Manual - Free download as PDF File (. Request a quote Find a dealer. 5 yd³. The acquisition of ABS would. or wiring harness. coalrulz said: KCORNISH, Most of the Komatsu fault codes are 6 digits in length. また、メイン画面には、標準装備のKomVision（機械周囲カメラシステム）による機械周囲のカメラ画像を大きく表示し. This complete service repair workshop manual PDF download for the PC490LC-11 Komatsu Hydraulic Excavator (S/N: 85001 and up) has easy to read text sections with top quality diagrams, pictures and illustrations. 2B61MW INTER AXLE DIFFERENTIAL LOCK CLUTCH + SLIP. com, and get information about flight arrival and departure times, airport delays and airport information. This Complete Service Repair Workshop Manual PDF Download for the Komatsu WA200-7 (SN: 80001 and up) Wheel Loader has easy to read text sections with top quality diagrams, pictures and illustrations. The scale of RC construction truck is 1/24, and with powerful motor. It's on a 2013 Komatsu PC490LC -7. Komatsu Ltd. 36. None. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright. 解像度で視認性に優れた高精細7インチ液晶ディスプレイを採用。. With continuous camera view (522 pages) Excavators Komatsu PC210LC-6K Operation & Maintenance Manual. It's the same service manual used by dealers that guaranteed to be fully functional and intact without any missing page to save. CA122, the intake air. Komatsu PC5500-6 Hydraulic Mining Shovel Service Repair Manual (SN 15035 and up) June 26, 2020 JCB JS290 - Tier III Auto Tracked Excavator Service Repair Manual SN 01421200 to 01421599CEBM027700. Cause Procedure, measuring location, criteria and remarks 4 Defective low-pressure circuit component • For check of pressure in fuel low pressure circuit, see TESTING AND AD- 30 Testing and adjusting SEN00586-01 D65EX, PX, WX-15E0 21 CALL E03 DK31KB Steering potentiometer (2) Short circuit q S/T Electric system E01 DK40KA Brake potentiometer Disconnection S/T Electric system Jan 20, 2021. No worries, most likely someone shut the master. Komatsu's range of construction, mining, forestry and manufacturing equipment provide a durability and reliability that’s second to none, and we’ll continue to help our customers meet their business goals with high-quality equipment that improves production and lowers operation costs. 0 to 15 yd3. Always keep. DB2AMA. 2012/01) • The Komatsu Variable Geometry Turbocharger (KVGT) consists of more precise parts (variable mechanism) than the parts used in the conventional turbocharger. CEBM026702. Covers: Komatsu WA270-7 Wheel Loader (USA, Serial No. txt) or read book online for free. US Dollar: $55. 85463. N 450001 and UP] [This is true Electronic pdf copy with contains high quality images and diagrams, not scanned version] Contents of this Workshop Manual. Threats include any threat of suicide, violence, or harm to another. com. FILE DETAILS: Komatsu Wheel Loader WA500-7 Shop Manual A94001 and up. Este mes, el 22 de octubre de 2023, ocurrirá un fenómeno que se manifiesta cada 19. Find latest flight arrivals & departures and other travel information. EOE, a network failure. Anderson Equipment offers. Purchase your next favourite publicationKomatsu locator. Occasionally the Dreaded L04 Error code might pop up on the screen when you are about to start the Komatsu based Bayshore Systems Drill Rig. Have Kamatzu 37-P~2 left brake does not work I also have a. The step by step instructions show you how to fault find or complete any repair or overhaul, correctly and efficiently,all Komatsu Fault Codes List by isoscell9isoscell. This complete service repair workshop manual PDF download for the PC290LC-11 Komatsu Hydraulic Excavator (SN: 35001 and up) has easy to read text sections with top quality diagrams, pictures and illustrations. Department of Neuroscience and Regenerative Medicine. SEN05650-01. Komatsu Hydraulic Excavator PC490LC-10, PC490LC-11, PC490LCi-11 workshop service repair manual. Komatsu Wheel Loader WA380-, WA380Z-series workshop service repair manual includes:Man in custody, accused of shooting one person and stabbing and shooting another in Rankin County WAPT. The Americas - Global Operations. Plug into this machine with the appropriate diagnostic software so you can do more in depth diagnostics and monitor. El GPS proporciona información horaria precisa al contar el número de segundos en una semana, y este […]Cargador Komatsu WA 380 Manual PDF | PDF | Transmisión (Mecánica) | Relé. EOE, a network failure. (formerly Joy Global Inc. This material is proprietary to Komatsu America Corp. checking the machine without shutting down the When removing the track, it separates suddenly. Find what works for you. SPN: 627. See if your flight has been delayed or cancelled and track the live position on a map. . 「よくあるご質問（FAQ）」ページです。. When you need to push a large amount of material, our dozers have been engineered to be a workhorse of your fleet. Small excavators Mid-size excavators Large excavators Surface mining excavators IMC Excavators. Category. Browse short-form content that's perfect for a quick read. . 56 yd 3 and excellent power with dimensions making it transportable. Operating weight 76,897 - 77,856 lbs. All specifications and tolerances are listed. (2) To execute contracts with customers. 1]Pull off hub (3) and then remove thrust plate (4). 18 full service locations. (3) To comply with its legal or regulatory obligations. 必要な情報をより見やすく分かりやすい画面にデザインしました。. 2. The Shop Manual describes the effective and safe servicing and repair methods recommended by Komatsu. 732 Failure code [CA1228] (Abnormal EGR valve servo 1). 操作スイッチ数の少ない表示装置であっても、操作スイッチに警報出力の解除機能を割り付けることができる作業車両の表示装置及びその表示方法並びに作業車両を提供するため、作業車両の稼働状態の表示を行う表示部31の表示画面と、前記表示画面の表示切替を行う操作部32とを備えた作業. Anderson Equipment offers. Find what works for you. #1. for the . AC Condenser for 2003-2007 Honda Accord 4-door Sedan 80110sdaa02. FMI: 2/2. 48 - 1. REMARK Provide an container to receive a quantity of hydraulic oil. WA380-6 mounts the SAA6D107E-1 engine. Get the most up-to-date information before you start any work. com with discounts and promotions. Compatibility: Windows/Mac/Tablet. This complete service repair workshop manual PDF download for the Komatsu PC490LC-11 Hydraulic Excavator (S/N: A41001 and up) has easy to read text sections with top quality diagrams, pictures and illustrations. View all specs. For versatility and high production consider the PC360LC-11 large excavator — it combines bucket capacity up to 2. 40-30 Connectorlistandlayout. Thunder bay ON. 「PC170LC-11」ページです。. TOP 商品情報 建設機械 油圧ショベル 中小型. Small dozers Mid-size dozers Large dozers Surface mining dozers. Insert the connector securely until a click is connector (3) in the direction of the arrow. 6D107E-2. It is the most realistic replica of a construction truck. pdf), Text File (. 4. Fine tuning improves on prompt design and few-shot learning by allowing you to train a model on a significant higher number of examples, a number which would otherwise. KOMATSU. Security Center. Distance Flown--Economy. Hydraulic technical information subscribe to my channel for more information and videos, Also press the bell icon so that you don't miss any updates. Labor: 1. entered on rear side. N 450001 and UP] [This is true Electronic pdf copy with contains high quality images and diagrams, not scanned version] Contents of this Workshop Manual. KOMATSU. DB29KQ. makes efforts below based on the belief that the proper protection of personal information is a corporate social responsibility. and is not to be. (Rev. . . $9. fujsekmdidjd3e • 3 views. 00-29 how to read the shop manual. 1,338 satisfied customers. Close suggestions Search Search. WA380-6 SEN00124-01. If foreign material enters this system, it may cause a failure. L&T-KOMATSU PC210-8 MONITOR, complete function troubleshoot ENGINE ECU, ELECTRICAL WORK for Wiring harness Electric & Electronic ☎️9866905244. This Complete Service Repair Workshop Manual PDF Download for the Komatsu WA380-6 Wheel Loader (SN: H60051 and up) has easy to read text sections with top quali. It is the world's first hybrid (electro-hydraulic) powered construction equipment. . There are two that supply the engine control processor. #4. 作品名：美しすぎて、目を合わせられない―。小松杏 AV DEBUT品 番：JUL-538發行日：2021/04/25女優名：小松 杏(Komatsu-An)事務所. . You should also check all the fuses. 「商品情報」では充実の商品ラインナップで、お客さまへの最適なソリューションをご提案します。. For ease of understanding, the manual is divided into the following sections. I would check. May 7th, 2023, 7:55 PM PDT. The step by step instructions show you how to fault find or complete any repair or overhaul, correctly and efficiently, saving time and avoiding. . Supply voltage to the ECM fell below +6. Takeshi Horikoshi, chief financial officer at Komatsu, discusses the company's business strategy and says there's no sign of a recovery in China's. The PX model has a high-capacity, high-wear resistant dozer. Anytime you have a regulatory or after treatment system related fault code of that exist and it has been identified as well as resolved, the after treatment system components would need to be reset within the software and potentially some software updates performed at the dealer level in order to reset the system if there were any type of derate that existed. ENGINE. Failure codes list 1. • If the engine. and is not to be reproduced, used, or disclosed except in accordance with written authorization from. . komatsu pc310-10. I don't have a Dash 7 book but my Dash 11 books shows that code to be. Thunder bay ON. View Details. Overview. txt) or read book online for free. Cargador Komatsu WA 380 Manual PDF | PDF | Transmisión (Mecánica) | Relé. index 00 index and foreword 00-1 abbreviation list 00-21 foreword, safety,. I would check to see if the machine will complete a successful regeneration. Read Komatsu WA380-7 Wheel Loader Service Repair Manual SN10001 and up by kmd9isbnvumk on Issuu and browse thousands of other publications on our p. Source voltage reduction/input (KK) CALL E04. . Compare size, weight and detailed tech specifications for similar Hydraulic Excavator. Komatsu d65 px 17 dozer bulldozer service repair manual sn 1001 and up - Download as a PDF or view online for free. This video is going to give you “the operator” insight about what you need to do while operating Komatsu equipment with Tier IV Interim machines equipped wit. He said it also asks for regen. -. Language : English Pages : 3922 Downloadable : Yes File Type : PDF Size: 116 MB. Functions of components and systems are also explained. FMI: 2/2 ECM fell momentarily, or the ECM monitor data can be inaccurate. This complete service repair workshop manual PDF download for the PC240LC-11 Komatsu Hydraulic Excavator (SN: A22001 and up) has easy to read text sections with top quality diagrams, pictures and illustrations. Seller Dashboard; Blog; Contact Us; Login; Search. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Komatsu 12v140e-3 Series Engine Service Manual Fuel Type: Komatsu engines can run on various types of fuel, such as diesel or natural gas. コマツといっしょに、ICT. pdf), Text File (. Open navigation menu. All specifications and tolerances are listed. 操作スイッチ数の少ない表示装置であっても、操作スイッチに警報出力の解除機能を割り付けることができる作業車両の表示装置及びその表示方法並びに作業車両を提供するため、作業車両の稼働状態の表示を行う表示部31の表示画面と、前記表示画面の表示切替を行う操作部32とを備えた作業. 6. . Join 9,360,000 engineers with over 4,850,000 free CAD files Join the Community. Look in the engine compartment for a harness that might of chaffed or corrosion, or possibly disconnected. NEWS AFTERMARKET 21 Jun 2023. Complete service repair manual with Electrical Wiring Diagrams for Komatsu Hydraulic Excavator PC490LC-10, PC490LC-11, PC490LCi-11, with all the technical information to maintain, diagnose, repair, rebuild like professional mechanics. across six states. 00 Índice y Prólogo GSN00123-05. You have a short in the wiring or a diode is blown. Skyjack 7127 7135 8243 & 9250 Engine Powered OPERATING MANUAL. txt) or read online for free. 20-468. 「商品情報」では充実の商品ラインナップで、お客さまへの最適なソリューションをご提案します。. E11-449 is a code for high rail pressure. Page 1 Operation & UENAM01165 Maintenance Manual PC290LC PC290NLC HYDRAULIC EXCAVATOR SERIAL NUMBERS PC290LC-11 - K70001 and up PC290NLC-11 - K70001 and up PC290LC-11 - 35001 and up PC290NLC-11 - 35001 and up WARNING Unsafe use of this machine may cause serious injury or ORIGINAL INSTRUCTIONS death. KOMATSU. Software. Failure code [CA1117. Check the water pump for belt pulley play, emerging grease and leaks. World-class products are backed by superior levels of service and support delivered by people who are passionate about performance and customer satisfaction. コマツといっしょに、ICT. privacy statement, for purposes that may include site operation, analytics, enhanced user experience, or advertising. Komatsu WA320-7 Wheel Loader Shop Manual (80001 and up) - SEN06202-01. PC210LC-10 HYDRAULIC EXCAVATOR SERIAL NUMBERS. • When draining oil, prepare a container with sufficient capacity. The Komatsu iSite version 1. 3-9. 3. Age. Seller Center. . ICT. The seller just lowered the price so far I just couldn't resist. . This manual makes any repair job easy to do with. The GD655-7 provides operators with an all-new, ergonomic working environment and the new spacious cab allows more room. A27001 and up) Pages: 2,048. (4) To protect its legitimate interests. Phone: (205) 708-7059. . 7kb: Download: Komatsu PC400-7 Diagnostic Trouble Codes [PDF] 67. 2 yd³. davecampbell said: Against my better judgement I bought a pc210 today that is displaying a code for high crankcase pressure. Adding this Standard D51PX-24 with loads of Premier warranty, Year 2021 Hours 3000 Located TEC/Tuscaloosa TEC Sales Price: $205,000. Detroit Office, Komatsu America Industries LLC. • After disconnecting the hoses or tubes, plug them to prevent dust from entering. 00. 日本企業によるウクライナ復興を支援する動きが相次いでいる。コマツは地雷除去機を提供し、兼松はがれき除去向けに油圧圧砕機を送る。日本. À présent, elle les a affi nés et combinés avec de nouvelles technologies afi n de produire le KTCS ultramoderne qui équipe tous les HM300-3. Price: US$ 99. Shop Manual Bulldozer Bulldozer D65EX-17 D65PX- 17 D65WX-17 Model D65EX-17 D65PX-17 D65WX-17. and parts in their correct places. com > Flights > Flights to Ordos > Flights from Beijing to Ordos > CA1117. Komatsu has a long history of building top quality, heavy-duty equipment. Plot 58, Gaborone, International Commerce Park, Private Bag 00137 Gaborone Botswana (267) 392-8343 (267) 392-8515. You seek a workplace that fosters a spirit of innovation and independence, allowing you to pursue new ideas and take the actions needed to reach the company’s goals as well as your own. Oil level gauge and oil filler tube 1) Remove bracket (1) and then remove oil filler tube (2). Recent All time. Apply for Financing. View all specs. If a foreign language manual is necessary, contact your local distributor for. Shop Manual Hm400-3 - Free ebook download as PDF File (. For other global mining offerings, select the globe icon at the top of this page for language options. We want you to meet your productivity targets, so we are pushing innovations in suspension, transmission, electric drive tech and autonomous operation. Esperamos que disfrutes este diseño renovado para que sigamos.