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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

Bulletins, newest first
SA-035-20b2021-01-06. Service bulletin. EQUIPMENT; 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.
MT-005-202020-12-03. Service bulletin. ENGINE AND ENGINE COOLING. Some customers may complain about high engine oil consumption. Before attempting any repairs, verify the complaint by using the guideline below to determine if an engine repair is necessary: Engine Oil Consumption Inspection Guideline 1. Record the vehicle mileage. 2. Engine at normal operating temperature, top off engine oil level to the full mark on the dipstick. 3. Ask the customer to return to the dealer after 1200 miles to recheck the engine oil level. 4. After 1200 miles, engine at normal operating temperature, check the engine oil level on the dipstick. 5. Is the engine oil level above the low mark on the dipstick? • Yes - No repair is necessary. • No - Proceed to MGSS online or Workshop Manual (section 01-03 NO. 16 HIGH OIL CONSUMPTION/LEAKAGE).
01-006-20-3695b2020-12-03. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. Some vehicle may exhibit a tapping noise from the engine during idling; etc., and synchronized to the engine rpm. The tapping noise may be caused by the switchable hydraulic lash adjuster (HLA), which may not work properly due to air bubbles accumulated in the oil passage in it.
SA-071-202020-11-04. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING. Currently, the instructions on MGSS recommend the use of Loctite 962T or equivalent when installing a SKYACTIV cylinder head, but it is no longer available. The following 3 adhesives are alternatives available as an equivalent to Loctite 962T: Loctite 272, Loctite 518 Threebond TB-1386H
SA-061-20a2020-10-05. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING. If you receive a customer concern about the CHECK IN light coming on and DTC P3400 (cylinder deactivation system malfunction) stored, the cylinder deactivation oil control valve may be plugged with plastic debris from the oil filter wrapper. The debris may enter the center of the oil filter when poking a hole in the filter wrapper during removal, and then travel through the engine and plug the cylinder deactivation oil control valve.
SA-058-20a2020-09-01. 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. NOTE: Cylinder head replacement requires MASH authorization.
SA-058-202020-08-05. 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.
01-008-20-36942020-07-02. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING; POWER TRAIN. Some customers may experience the CHECK ENGINE light ON with DTC P2229:00 stored in PCM memory. • P2229:00 (BARO sensor circuit high input). This concern will most likely occur on vehicles that have aftermarket wax applied in the engine compartment. Aftermarket wax applied in the engine compartment may adhere on the breather hole located at the bottom of the PCM, which may collect dust and result in a plugged filter. This breather hole is actually a filter for the air pressure sensor in the PCM. When the PCM gets hot, the internal air pressure may rise due to the plugged filter and result in DTC P2229:00. To eliminate this concern, the shape of the PCM bracket has been modified to not cover the breather hole and eliminate a gap between it and the PCM that may promote the residual liquid wax.
SA-040-20a2020-05-05. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; EQUIPMENT. Key Transmitter Power Saving Function: When the key transmitter Power Saving Function is turned ON, transmitter battery power consumption is restricted, thereby extending the transmitter battery life. IMPORTANT: • The engine will not start unless the key transmitter is held over the Start Stop button. • Outside door handle lock/unlock touch sensor is inoperative. • Key transmitter indicator lights are inoperative.The key transmitter control functions (i.e. locking/unlocking door, etc.) are operational when pressing the transmitter switches, even while the key power saving function is turned ON.
01-006-20-36952020-05-04. Service bulletin. ENGINE AND ENGINE COOLING. Some vehicle may exhibit a tapping noise from the engine during idling; etc., and synchronized to the engine rpm. The tapping noise may be caused by the switchable hydraulic lash adjuster (HLA), which may not work properly due to air bubbles accumulated in the oil passage in it.
SA-035-20a2020-04-06. 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.
00-001-20-36892020-04-03. Service bulletin. SERVICE BRAKES, HYDRAULIC; POWER TRAIN; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; ENGINE AND ENGINE COOLING. 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.
SA-035-202020-02-29. 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-009-202020-01-30. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; STRUCTURE. LACK OF POWER UNDER HEAVY LOAD WITH NO WARNING LIGHTS OR DTCS: 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.
SA-053-192019-12-21. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. GUIDE LINES AND PHOTOS TO DETERMINE IF FLUID/OIL SEEPAGE OR LEAK IS SEVERE ENOUGH TO REQUIRE WARRANTY REPAIR OR TO CLEAN AND MONITOR. Some customer's might state that they notice fluid or oil leaking/dripping on the ground when the vehicle is parked. For this concern, inspect the vehicle for any trace of a fluid or oil leak and use the following examples as a guide to determine if it is severe enough to require a repair, or just to clean the area and monitor it at the next service.
MT-002-192019-12-20. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT. If an engine assembly is replaced after a catastrophic internal mechanical failure, clean the intake manifold internally before installing a replacement engine assembly. If the intake manifold is not cleaned properly, the replacement engine may fail prematurely. Metallic debris from the old engine (with catastrophic internal mechanical failure) may rest inside the intake manifold. When the new engine assembly is installed, debris in the intake manifold will be ingested into the new engine and cause internal damage.
01-022-19-36572019-12-20. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; 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 Bulletin is to inform you about the water pump sealing mechanism and the criteria if replacement is necessary or not.
SA-012-19b2019-11-24. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT ADAPTIVE/MOBILITY. A valve tapping or knocking noise may be heard from the top end after the engine cools down (the vehicle is parked overnight) or after it has been idling for an extended time. The tapping noise will decreases as the vehicle is being driven or if the rpm is held above 2500-3000 RPM. This may be caused by the valve Hydraulic Lifters (HLA) bleeding down as the engine cools or when the engine has been idling for an extended period of time, creating excessive valve lash clearance.
MT-004-192019-11-24. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT; ELECTRICAL SYSTEM. Some customers may complain about: • Intermittent engine no start • Instrument cluster red security indicator light ON • Engine Start/Start Button Amber indicator light flashing • Battery discharge • Electrical relay buzzing noise • DTC B13D3:94 (Communication error with remote transmitter) stored.This may be caused by: • A key in a purse near a cell phone. The cell phone radio waves may interrupt the immobilizer system. • An aftermarket cell phone charger. The charger may produce electrical noise that interrupts the immobilizer system. • An aftermarket GPS tracker. Some aftermarket devices that are wired to the vehicles’s wiring harness may create unusual electrical symptoms.
SA-049-192019-11-21. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. Some customers may complain about a Mazda Mobile Start (MMS) system malfunction. Use the information below to troubleshoot the customers complaint: • MAZDA MOBILE START (MMS) TROUBLESHOOTING GUIDE • CANNOT COMMUNICATE WITH VEHICLE • ERROR MESSAGE INSTALLED ON ANDROID DEVICES • COMMUNICATION ERRORS • MMS CHECK MODE - Use to verify system operation (see below).

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.