{"product_id":"f21-1028-1391-genuine-paccar-hvac-climate-temperature-control-module","title":"F21-1028-1391 | Genuine Paccar HVAC Climate Temperature Control Module","description":"\u003cp\u003e\u003cstrong\u003eDescription:\u003cbr\u003e\u003c\/strong\u003eAn HVAC Climate Temperature Control Module\u003cstrong\u003e F21-1028-1391\u003c\/strong\u003e is the electronic unit that controls your vehicle’s heating, ventilation, and air conditioning (HVAC) system. HVAC Climate Temperature Control Module For Kenworth T680, T880, T660 Peterbilt 579, 576.\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003ePart Number\u003c\/strong\u003e: F21-1028-1391\u003cbr\u003e\u003cstrong\u003eCondition\u003c\/strong\u003e\u003cspan\u003e: New\u003c\/span\u003e\u003cbr\u003e\u003cstrong\u003eManufacture\/Brand\u003c\/strong\u003e\u003cspan\u003e: Paccar\u003cbr\u003e\u003c\/span\u003e\u003cstrong data-end=\"176\" data-start=\"160\"\u003e\u003cspan\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/strong\u003e\u003cstrong\u003eFits F21-1028-1391 \u003c\/strong\u003eFor \u003cbr\u003e\u003c\/p\u003e\n\u003ctable width=\"100%\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp data-end=\"275\" data-start=\"253\" data-section-id=\"1ame40z\"\u003e\u003cstrong\u003e  Kenworth trucks\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-end=\"421\" data-start=\"276\"\u003e\n\u003cli data-end=\"317\" data-start=\"276\" data-section-id=\"17wgcs5\"\u003e\u003cspan class=\"hover:entity-accent entity-underline inline cursor-pointer align-baseline\"\u003e\u003cspan class=\"whitespace-normal\"\u003eKenworth T680\u003c\/span\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli data-end=\"359\" data-start=\"318\" data-section-id=\"1gcjogl\"\u003e\u003cspan class=\"hover:entity-accent entity-underline inline cursor-pointer align-baseline\"\u003e\u003cspan class=\"whitespace-normal\"\u003eKenworth T880\u003c\/span\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli data-end=\"421\" data-start=\"360\" data-section-id=\"ebz8rn\"\u003e\n\u003cspan class=\"hover:entity-accent entity-underline inline cursor-pointer align-baseline\"\u003e\u003cspan class=\"whitespace-normal\"\u003eKenworth T660\u003c\/span\u003e\u003c\/span\u003e (some configurations)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-end=\"531\" data-start=\"508\" data-section-id=\"1pjhz2o\"\u003e  \u003cstrong\u003ePeterbilt trucks\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-end=\"674\" data-start=\"532\"\u003e\n\u003cli data-end=\"573\" data-start=\"532\" data-section-id=\"hjs5dh\"\u003e\u003cspan class=\"hover:entity-accent entity-underline inline cursor-pointer align-baseline\"\u003e\u003cspan class=\"whitespace-normal\"\u003ePeterbilt 579\u003c\/span\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli data-end=\"615\" data-start=\"574\" data-section-id=\"pzvh1x\"\u003e\u003cspan class=\"hover:entity-accent entity-underline inline cursor-pointer align-baseline\"\u003e\u003cspan class=\"whitespace-normal\"\u003ePeterbilt 567\u003c\/span\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003cli data-end=\"674\" data-start=\"616\" data-section-id=\"1iw1wsg\"\u003eOther modern Peterbilt models with PACCAR HVAC systems\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cul class=\"nav catalog\" id=\"catalogModels\"\u003e\u003c\/ul\u003e\n\u003cp data-end=\"353\" data-start=\"160\"\u003e\u003cstrong\u003ePurpose of using F21-1028-1391:\u003cbr\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003ctable width=\"100%\" style=\"height: 35.5972px;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"height: 35.5972px;\"\u003e\n\u003ctd style=\"height: 35.5972px;\"\u003e\n\u003cp data-section-id=\"ma1fau\" data-start=\"217\" data-end=\"256\"\u003e \u003cstrong\u003e1. Maintain desired temperature\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"257\" data-end=\"370\"\u003e\n\u003cli data-section-id=\"1rsj616\" data-start=\"257\" data-end=\"296\"\u003eLets you set a specific temperature\u003c\/li\u003e\n\u003cli data-section-id=\"1328yqx\" data-start=\"297\" data-end=\"370\"\u003eThe module automatically adjusts heating or cooling to keep it steady\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"1hj1ruc\" data-start=\"377\" data-end=\"425\"\u003e \u003cstrong\u003e2. Control heating and air conditioning\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"426\" data-end=\"555\"\u003e\n\u003cli data-section-id=\"o2dtbq\" data-start=\"426\" data-end=\"457\"\u003eTurns the A\/C system on\/off\u003c\/li\u003e\n\u003cli data-section-id=\"15po2pa\" data-start=\"458\" data-end=\"506\"\u003eRegulates heat from the engine (heater core)\u003c\/li\u003e\n\u003cli data-section-id=\"8jd4u8\" data-start=\"507\" data-end=\"555\"\u003eMixes hot and cold air for the right balance\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"djn9qa\" data-start=\"562\" data-end=\"600\"\u003e \u003cstrong\u003e3. Manage airflow and fan speed\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"601\" data-end=\"686\"\u003e\n\u003cli data-section-id=\"1aejogp\" data-start=\"601\" data-end=\"638\"\u003eControls how strong the air blows\u003c\/li\u003e\n\u003cli data-section-id=\"jlfqkf\" data-start=\"639\" data-end=\"686\"\u003eAdjusts fan speed automatically or manually\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"1a727ow\" data-start=\"693\" data-end=\"726\"\u003e \u003cstrong\u003e4. Direct air where needed\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"727\" data-end=\"803\"\u003e\n\u003cli data-section-id=\"fkurbe\" data-start=\"727\" data-end=\"803\"\u003eSends air to:\n\u003cul data-start=\"745\" data-end=\"803\"\u003e\n\u003cli data-section-id=\"sjp9ee\" data-start=\"745\" data-end=\"764\"\u003eDashboard vents\u003c\/li\u003e\n\u003cli data-section-id=\"12l4iq8\" data-start=\"767\" data-end=\"776\"\u003eFloor\u003c\/li\u003e\n\u003cli data-section-id=\"1w1j17j\" data-start=\"779\" data-end=\"803\"\u003eWindshield (defrost)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"jnvjxi\" data-start=\"810\" data-end=\"853\"\u003e \u003cstrong\u003e5. Improve driver comfort and safety\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"854\" data-end=\"913\"\u003eIn vehicles like the \u003cspan class=\"hover:entity-accent entity-underline inline cursor-pointer align-baseline\"\u003e\u003cspan class=\"whitespace-normal\"\u003eKenworth T680\u003c\/span\u003e\u003c\/span\u003e:\u003c\/p\u003e\n\u003cul data-start=\"914\" data-end=\"1050\"\u003e\n\u003cli data-section-id=\"13rtudf\" data-start=\"914\" data-end=\"958\"\u003eKeeps the cab comfortable in all weather\u003c\/li\u003e\n\u003cli data-section-id=\"hrx7rd\" data-start=\"959\" data-end=\"1009\"\u003ePrevents windshield fogging (defrost function)\u003c\/li\u003e\n\u003cli data-section-id=\"1ojkdbj\" data-start=\"1010\" data-end=\"1050\"\u003eReduces driver fatigue on long trips\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"1bilxh2\" data-start=\"1057\" data-end=\"1099\"\u003e \u003cstrong\u003e6. Enable automatic climate control\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"1100\" data-end=\"1214\"\u003e\n\u003cli data-section-id=\"1lvhxab\" data-start=\"1100\" data-end=\"1154\"\u003eUses sensors (inside temp, outside temp, sunlight)\u003c\/li\u003e\n\u003cli data-section-id=\"tky0ue\" data-start=\"1155\" data-end=\"1214\"\u003eAdjusts everything automatically without constant input\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"v9s8b9\" data-start=\"1221\" data-end=\"1256\"\u003e \u003cstrong\u003e7. Optimize system efficiency\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"1257\" data-end=\"1344\"\u003e\n\u003cli data-section-id=\"1s5nete\" data-start=\"1257\" data-end=\"1300\"\u003ePrevents unnecessary A\/C or heating use\u003c\/li\u003e\n\u003cli data-section-id=\"1xop8ve\" data-start=\"1301\" data-end=\"1344\"\u003eHelps reduce fuel or energy consumption\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp data-end=\"353\" data-start=\"160\"\u003e\u003cstrong\u003e\u003cbr\u003e\u003c\/strong\u003e\u003cstrong data-end=\"597\" data-start=\"585\"\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eSigns of a Bad HVAC Climate Temperature Control Module F21-1028-1391:\u003cbr\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003ctable width=\"100%\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp data-section-id=\"117jroa\" data-start=\"252\" data-end=\"287\"\u003e \u003cstrong\u003e1. Temperature won’t change\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"288\" data-end=\"387\"\u003e\n\u003cli data-section-id=\"1tqmyqc\" data-start=\"288\" data-end=\"335\"\u003eStuck blowing \u003cstrong data-start=\"304\" data-end=\"333\"\u003eonly hot or only cold air\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"6ax3l6\" data-start=\"336\" data-end=\"387\"\u003eNo response when adjusting temperature settings\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"46mvia\" data-start=\"394\" data-end=\"421\"\u003e \u003cstrong\u003e2. Fan\/blower issues\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"422\" data-end=\"507\"\u003e\n\u003cli data-section-id=\"ol391d\" data-start=\"422\" data-end=\"448\"\u003eFan not working at all\u003c\/li\u003e\n\u003cli data-section-id=\"nkimto\" data-start=\"449\" data-end=\"476\"\u003eOnly works on one speed\u003c\/li\u003e\n\u003cli data-section-id=\"5keybh\" data-start=\"477\" data-end=\"507\"\u003eFan speed changes randomly\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"1off9bi\" data-start=\"514\" data-end=\"553\"\u003e \u003cstrong\u003e3. Airflow stuck in one position\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"554\" data-end=\"660\"\u003e\n\u003cli data-section-id=\"1ov2kxe\" data-start=\"554\" data-end=\"607\"\u003eAir only comes from one area (e.g., defrost only)\u003c\/li\u003e\n\u003cli data-section-id=\"14vvu3p\" data-start=\"608\" data-end=\"660\"\u003eCan’t switch between vents, floor, or windshield\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"1vlwb1v\" data-start=\"667\" data-end=\"695\"\u003e \u003cstrong\u003e4. A\/C not turning on\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"696\" data-end=\"767\"\u003e\n\u003cli data-section-id=\"drfd7p\" data-start=\"696\" data-end=\"737\"\u003eNo cold air even when A\/C is selected\u003c\/li\u003e\n\u003cli data-section-id=\"1q7i1pe\" data-start=\"738\" data-end=\"767\"\u003eCompressor doesn’t engage\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"wvg8qz\" data-start=\"774\" data-end=\"805\"\u003e \u003cstrong\u003e5. Unresponsive controls\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"806\" data-end=\"896\"\u003e\n\u003cli data-section-id=\"ecxg1n\" data-start=\"806\" data-end=\"854\"\u003eButtons, knobs, or touchscreen don’t respond\u003c\/li\u003e\n\u003cli data-section-id=\"i0t06e\" data-start=\"855\" data-end=\"896\"\u003eDelayed or erratic response to inputs\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"1ysefnx\" data-start=\"903\" data-end=\"935\"\u003e \u003cstrong\u003e6. Intermittent operation\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"936\" data-end=\"1014\"\u003e\n\u003cli data-section-id=\"1qh31hc\" data-start=\"936\" data-end=\"976\"\u003eWorks sometimes, then suddenly stops\u003c\/li\u003e\n\u003cli data-section-id=\"1dgmsch\" data-start=\"977\" data-end=\"1014\"\u003eMay change behavior while driving\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"1yohy5s\" data-start=\"1021\" data-end=\"1067\"\u003e \u003cstrong\u003e7. Incorrect or fluctuating temperature\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"1068\" data-end=\"1146\"\u003e\n\u003cli data-section-id=\"147muqp\" data-start=\"1068\" data-end=\"1115\"\u003eCabin temperature doesn’t match the setting\u003c\/li\u003e\n\u003cli data-section-id=\"8ddp1i\" data-start=\"1116\" data-end=\"1146\"\u003eRandom hot\/cold air swings\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"1hjxw6j\" data-start=\"1153\" data-end=\"1192\"\u003e \u003cstrong\u003e8. Warning lights or fault codes\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"1193\" data-end=\"1286\"\u003e\n\u003cli data-section-id=\"vt3ybm\" data-start=\"1193\" data-end=\"1242\"\u003eHVAC-related error codes (in modern vehicles)\u003c\/li\u003e\n\u003cli data-section-id=\"pul5m5\" data-start=\"1243\" data-end=\"1286\"\u003eCommunication issues with other modules\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-section-id=\"12sc1pp\" data-start=\"1293\" data-end=\"1320\"\u003e \u003cstrong\u003e9. Electrical issues\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"1321\" data-end=\"1389\"\u003e\n\u003cli data-section-id=\"vlusj2\" data-start=\"1321\" data-end=\"1352\"\u003eBlown fuses related to HVAC\u003c\/li\u003e\n\u003cli data-section-id=\"13hyn3u\" data-start=\"1353\" data-end=\"1389\"\u003eBurning smell (rare but serious)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp data-end=\"476\" data-start=\"97\"\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan style=\"font-size: 0.875rem;\"\u003eAbout the Manufacturer – \u003c\/span\u003e\u003cspan style=\"font-size: 0.875rem;\"\u003ePaccar:\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-end=\"381\" data-start=\"0\"\u003e\u003cstrong data-start=\"96\" data-end=\"110\"\u003ePACCAR Inc\u003c\/strong\u003e is a global technology leader in the design, manufacture, and customer support of premium light-, medium-, and heavy-duty trucks. Founded in 1905 and headquartered in Bellevue, Washington, PACCAR is best known for its world-class truck brands: Kenworth, Peterbilt, and DAF.\u003cbr\u003ePACCAR’s trucks are recognized for their durability, fuel efficiency, advanced engineering, and driver-focused technology. In addition to truck manufacturing, PACCAR also designs and builds diesel engines, and provides financial services, information technology, and aftermarket support to its global customer base.\u003c\/p\u003e","brand":"Paccar®","offers":[{"title":"Default Title","offer_id":50682827014391,"sku":"F21-1028-1391","price":599.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0895\/7080\/3959\/files\/photo_2026-04-16_00-35-37.jpg?v=1776289077","url":"https:\/\/forcetruckparts.com\/products\/f21-1028-1391-genuine-paccar-hvac-climate-temperature-control-module","provider":"Force Truck Parts","version":"1.0","type":"link"}