Service bulletins for the 2020 Mazda Mazda6
A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.
364 on file from NHTSA, as of 2026-10-19.
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Only bulletins with component: Engine are shown. Show all
| SA-011-24 | 2024-03-06. Service bulletin. STEERING; SERVICE BRAKES, HYDRAULIC; WHEELS; TIRES; ENGINE AND ENGINE COOLING; POWER TRAIN. Mazda has developed factory recommended scheduled maintenance services that support all major vehicle systems. Mazda recommends dealers follow the scheduled maintenance tables as cited in the vehicle-specific workshop manual or owner's manual. Services performed outside of Mazda's factory scheduled maintenance are not recommended. These services are unnecessary and create unneeded expenses for your customers. |
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| 01-005-23a | 2024-01-06. Service bulletin. ENGINE AND ENGINE COOLING. Some customers may experience the check engine light ON with DTC P0126:00 (Thermostat stuck open) and one or more of the following symptoms: The engine takes longer to warm up The engine temperature gauge fluctuates The low coolant temperature indicator (blue) light stays on longer or comes on while driving Poor heater performance, especially at idle |
| SA-081-23 | 2024-01-06. Service bulletin. ENGINE AND ENGINE COOLING. There is a concern that some water pumps are being replaced that are not faulty, due to signs of a very small coolant leak from the bleed hole. This Service Alert is to inform you about the water pump sealing mechanism and the criteria if replacement is necessary or not. |
| SA-032-23a | 2023-11-02. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. If you encounter any type of electrical concern (e.g, dead battery, engine no start, DTC(s) stored...), interview the customer before proceeding with normal MGSS diagnosis by asking if any aftermarket devices have been installed. Aftermarket devices may be the cause of the electrical concern. Below are a few examples of unusual electrical concerns caused by aftermarket devices. |
| SA-037-23a | 2023-09-03. Service bulletin. ENGINE AND ENGINE COOLING. A new cylinder head assembly for service parts has been newly established for SKYACTIV-G 2.5 with cylinder deactivation when replacement is needed. Valves, valve springs, valve spring seats, and cotters (IN/EX) are included in the new assembly. Dealers can now utilize the Limited Parts Ordering (LPO) page on eMDCS to order the repair parts for 2.5L (with cylinder deactivation) and 2.5L turbo cylinder head repairs. Hotline and MASH authorization is not required to order parts for performing this repair. If there are any questions on part ordering or part status, contact the DAG group for assistance. |
| SA-037-23 | 2023-07-05. Service bulletin. ENGINE AND ENGINE COOLING. A new cylinder head assembly for service parts has been newly established for SKYACTIV-G 2.5 with cylinder deactivation when replacement is needed. Valves, valve springs, valve spring seats, and cotters (IN/EX) are included in the new assembly. Dealers can now utilize the Limited Parts Ordering (LPO) page on eMDCS to order the repair parts for 2.5L (with cylinder deactivation) and 2.5L turbo cylinder head repairs. Hotline and MASH authorization is not required to order parts for performing this repair. If there are any questions on part ordering or part status, contact the DAG group for assistance. |
| SA-035-23 | 2023-07-05. Service bulletin. ENGINE AND ENGINE COOLING. Some customers may complain of a lack of power under heavy load without any warning lights or DTCs. This concern may be due to a loose or detached hood weatherstrip, which can cause a blockage or restriction in the air intake system. |
| 01-008-23 | 2023-07-05. Service bulletin. ENGINE AND ENGINE COOLING. Some vehicles may exhibit oil leakage from the drive belt auto tensioner and rattling noises from the engine compartment. This may be caused by insufficient sealing at the drive belt auto tensioner damper when the auto tensioner fully operates under both high ambient temperature and high load conditions. To eliminate this concern, the shape of the drive belt auto tensioner damper has been changed. |
| SA-032-23 | 2023-06-04. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. If you encounter any type of electrical concern (e.g, dead battery, engine no start, DTC(s) stored...), interview the customer before proceeding with normal MGSS diagnosis by asking if any aftermarket devices have been installed. Aftermarket devices may be the cause of the electrical concern. Below are a few examples of unusual electrical concerns caused by aftermarket devices. |
| 01-006-23 | 2023-05-03. Service bulletin. ENGINE AND ENGINE COOLING. Some vehicles may exhibit oil seepage or oil leak onto the engine front cover, which becomes more apparent with dust adhesion. |
| SA-010-23 | 2023-03-03. Service bulletin. ENGINE AND ENGINE COOLING; VISIBILITY; EXTERIOR LIGHTING; SERVICE BRAKES, HYDRAULIC; ELECTRICAL SYSTEM. Some customers may experience one or more electrical malfunctions after a vehicle body repair. The newly painted fender stay (2) may be causing a poor front harness (1) ground connection. |
| 01-005-23 | 2023-03-03. Service bulletin. ENGINE AND ENGINE COOLING. Some customers may experience the check engine light ON with DTC P0126:00 (Thermostat stuck open) and one or more of the following symptoms: The engine takes longer to warm up. The engine temperature gauge fluctuates. The low coolant temperature indicator (blue) light stays on longer or comes on while driving. Poor heater performance, especially at idle. NOTE: Vehicles with SKYACTIV-G 2.5T are not applicable. If DTC P2B61:00 (Coolant control valve circuit range/performance) accompanies DTC P0126:00, this TSB is not applicable. Diagnose according to the instructions on MGSS online. Due to production variety of the failsafe thermostat integrated in the coolant control valve, engine coolant may enter into a dry hollow in the failsafe thermostat, resulting in unintended opening of the failsafe thermostat at lower temperatures (104-176 °F (40-80 °C)). To eliminate this concern, the production process of the coolant control valve has been modified. |
| 01-004-23 | 2023-03-03. Service bulletin. ENGINE AND ENGINE COOLING. Some vehicles may have the check engine light on with DTC P0524:00 or P055F:00 stored in memory. Contamination in the engine oil may cause the engine oil solenoid valve to become stuck, resulting in improper operation of the oil pump and improper oil pressure. DTC P0524:00 (Engine oil pressure too low), DTC P055F:00 (Engine oil pressure malfunction). The control software of the PCM has been modified to eliminate this concern. In addition, the production process has been modified to reduce contamination in the engine oil solenoid valve, oil pump, spacer and oil filter. |
| 01-002-23a | 2023-03-03. Service bulletin. ENGINE AND ENGINE COOLING; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. Some vehicles may have coolant leaks at the cylinder head around the exhaust manifold (as shown below). There may be cracks at the stud bolt hole (1) or at the outside of the exhaust manifold flange (2) on the cylinder head. |
| 01-001-23a | 2023-03-03. Service bulletin. ENGINE AND ENGINE COOLING. Some customers may complain about a poor acceleration and rough idling or the CHECK ENGINE light ON with DTC P0301:00, P0302:00, P0303:00, P0304:00.NOTE: Only turbo engines are applicable; non-turbo engines are NOT applicable. In most cases, DTCs P030X stores, but sometimes not. Sometimes the CHECK ENGINE light does not recognize this engine concern. This is caused by the variable valve in the exhaust manifold seizing and causing the exhaust port to become hot and the exhaust valve seat to wear unevenly, resulting in compression leakage. To eliminate this concern, the design of the exhaust manifold has been modified. |
| 01-002-23 | 2023-02-02. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM; ENGINE AND ENGINE COOLING. Some vehicles may have coolant leaks at the cylinder head around the exhaust manifold (as shown below). There may be cracks at the stud bolt hole or at the outside of the exhaust manifold. Cracks may be caused by: - Deformation of the exhaust manifold during usage causing unexpected force to certain areas of the cylinder head. - Residual stress generated during production in the cylinder head material may be greater than expected. The external force from the exhaust system when driving over bumps may cause unexpected force to certain areas of the cylinder head. To eliminate this concern, the design of the exhaust manifold gasket and the cylinder head has been modified to reduce the force on the cylinder head. |
| 01-001-23 | 2023-02-02. Service bulletin. ENGINE AND ENGINE COOLING. Some customers may complain about a poor acceleration and rough idling or the CHECK ENGINE light ON with DTC P030X:00 (only turbo engines are applicable; non-turbo engines are NOT applicable). - In most cases, P030X is stored, but sometimes not. - Sometimes the CHECK ENGINE light does not recognize this engine concern. This is caused by the variable valve in the exhaust manifold seizing and causing the exhaust port to become hot and the exhaust valve seat to wear unevenly, resulting in compression leakage. To eliminate this concern, the design of the exhaust manifold has been modified. |
| RF-23-01 | 2023-02-02. Service bulletin. ENGINE AND ENGINE COOLING. When servicing SKYACTIV engine vehicles requiring to replace the Oil Galley Plug and Crush Washer, order the required part numbers below. These parts are not listed in GEPC and were previously listed as "non-serviceable" in the cylinder block diagram. |
| MT-004-22 | 2023-01-05. Service bulletin. ENGINE AND ENGINE COOLING. Some vehicles may experience the Check Engine Light ON with DTC P0171 (Fuel Trim too Lean) and possibly DTCs P030X (Misfire). Vehicles having this concern should use the following Inspection/Repair procedure. |
| 01-013-22 | 2022-11-04. Service bulletin. ENGINE AND ENGINE COOLING. Some customers may experience the CHECK ENGINE light ON with DTC P0126:00 (Thermostat stuck open) and one or more of the following symptoms: * The engine takes longer to warm up * The engine temperature gauge fluctuates * The low coolant temperature indicator (blue) light stays on longer or comes on while driving * Poor heater performance, especially at idle NOTE: * Vehicles with SKYACTIV-G 2.5T are not applicable. * If DTC P2B61:00 (Coolant control valve circuit range/performance) accompanies, this information is not applicable. Diagnose according to the instructions in MGSS. Due to production variety of the failsafe thermostat integrated in the coolant control valve, engine coolant may enter into a dry hollow in the failsafe thermostat, resulting in unintended opening of the failsafe thermostat at lower temperatures (104-176 °F (40-80 °C)). To eliminate this concern, the production process of the coolant control valve has been modified. |
| 01-012-22 | 2022-11-04. Service bulletin. ENGINE AND ENGINE COOLING. Some vehicles may exhibit accumulation of dried coolant (1) around the water pipe (2). This is caused by a gap between the housing and pipe due to a press fitting during the manufacturing process. The accumulated coolant is solidified and plugs the gap in high temperature environment and the seepage is stopped and does not progress. This is normal and does not require a part replacement, clean off the dried coolant from around the pipe with a wire brush. |
| SA-065-22 | 2022-11-04. Service bulletin. ENGINE AND ENGINE COOLING. Some vehicles equipped with a coolant control valve may exhibit difficulties when refilling the coolant because the control valve is closed and air in the engine cannot escape during ignition ON. Therefore, turn the ignition OFF when refilling engine coolant using the radiator filler neck. |
| 01-007-22 | 2022-07-06. Service bulletin. ENGINE AND ENGINE COOLING. Some vehicles may have coolant leaks at the cylinder head around the exhaust manifold (as shown below). There may be cracks at the stud bolt hole or at the outside of the exhaust manifold. Cracks may be caused by: - Deformation of the exhaust manifold during usage causing unexpected force to certain areas of the cylinder head. - Residual stress generated during production in the cylinder head material may be greater than expected. The external force from the exhaust system when driving over bumps may cause unexpected force to certain areas of the cylinder head. To eliminate this concern, the design of the exhaust manifold gasket and the cylinder head has been modified to reduce the force on the cylinder head. |
| SA-018-22 | 2022-05-05. Service bulletin. ENGINE AND ENGINE COOLING. The WSM shows 3 possible crankshaft sprocket and timing chain combinations (Type A, B and C), but some vehicles have been produced with a combination of Type A timing chain with 2 yellow-colored links with a Type B crankshaft sprocket. |
| SA-013-22 | 2022-04-06. Service bulletin. ENGINE. A new cylinder head assembly for service parts has been newly established for SKYACTIV-G 2.5 with cylinder deactivation when replacement is needed. Valves, valve springs, valve spring seats, and cotters (IN/EX) are included in the new assembly. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.