WenmarOpen by Wenmar Pro

Service bulletins for the 2019 Mazda Mazda3

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.

827 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

By topic

Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
09-009-20-36652020-02-04. Service bulletin. ELECTRICAL SYSTEM; EXTERIOR LIGHTING. Some customers may notice that the rear turn lights only flash once instead of twice for the answer-back when a door unlock operation is performed using the remote transmitter button or the touch sensor. The concern occurs only once after the vehicle is in sleep mode (5 minutes or more after the doors are locked). This is caused by improper control logic of the electrical supply unit (ESU). To correct this issue, the ESU software has been modified.
SA-010-202020-01-30. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. TELEMATICS COMMUNICATION UNIT (TCU) INITIALIZATION PROCEDURE: When the Telematics Control Unit (TCU) replacement is necessary due to a failure, use MDARS to initialize the new TCU after replacement. Use the information in this service alert to initialize the new TCU until the procedure on MGSS is updated.
SA-008-202020-01-30. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; SERVICE BRAKES. INSTRUMENT CLUSTER WARNING MESSAGE "SAFETY AND DRIVER SUPPORT SYSTEMS PARTIALLY DISABLED" AND DTC U0401:68 IS STORED:Some customers may experience an instrument cluster warning message "Safety and Driver Support Systems Partially Disabled" and DTC U0401:68 [VEHICLE CONTROL MODULE (US)] (Error signal received from PCM, DSC HU/CM, instrument cluster, or body control module (BCM)) stored. This may be caused by the customer riding the brake pedal.
SA-006-202020-01-30. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; SERVICE BRAKES, HYDRAULIC; ELECTRICAL SYSTEM. WARNING MESSAGE SAFETY AND DRIVER SUPPORT SYSTEMS PARTIALLY DISABLED WITH DTC U2511:68: Some customer's may compain about warning message "Safety And Driver Support Systems Partially Disabled" with the following DTC's stored: • U2511:68 DSC - Error signal received from electrical supply unit (ESU) • U2511:68 VCM - Brake light control signal error. REPAIR PROCEDURE: • U2511:68 DSC - Error signal received from electrical supply unit (ESU) • Go to DTC U2511:68 [DSC HU/CM] • U2511:68 VCM - Brake light control signal error • Information is currently missing from Workshop Manual. MGSS will be updated soon. See service information below:
SA-003-202020-01-30. Service bulletin. ELECTRICAL SYSTEM. DTC U2050:55 STORED AFTER REPLACING OR REPROGRAMMING BCM:When the body control module (BCM) has been replaced or reprogrammed and the software is updated to the file names shown below, DTC U2050:55-BCM (Activation of remote control not implemented) may be stored in memory without any warning indication for the driver.
SA-002-202020-01-30. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. WIRELESS CHARGING PAD INSTALLATION INSTRUCTIONS CORRECTION: Section 6 of the Wireless Charging Pad instructions call for the use of an "ultrasonic cutter" to cut a rectangular hole for the harness to pass through and to serve as an access point to pop the wireless charger base out should service be required. Since an "ultrasonic cutter" is not readily available, follow the Repair Procedure to cut the rectangular hole.
SA-001-202020-01-30. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM. When performing Recall 4219L, make sure to connect a battery charger as stated in the Recall. If there are any issues, contact Hotline for assistance.
07-001-20-36602020-01-30. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:APPLIANCE:AIR CONDITIONER. Some customers may experience one side (driver side or passenger side) blowing warmer air out of the vents with the same or very close temperature settings for both sides when using the A/C and no DTCs related to the air conditioner system are stored in memory. This is caused by the air mix doors stopping operation during cranking and not recovering until the ignition is turned off. To correct this concern, the control software of the Dash-Electrical Supply Unit (Dash-ESU) has been modified.
09-003-20-36712020-01-23. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. In accordance with Federal regulations, follow the procedure listed below when replacing a speedometer. NOTE: Tampering with a motor vehicle odometer is strictly prohibited by Federal, and State laws. It is the dealer’s responsibility to comply with Federal, State, and local laws concerning odometer and related documentation requirements when providing a repair or replacement. • Mazda vehicles are manufactured with tamper-proof speedometers. • When a speedometer is replaced, the new speedometer will read zero (0) miles. • This procedure is extremely important to accurately represent actual vehicle mileage. • Prior to speedometer removal, complete the information required on the “Speedometer Replacement Label”. Labels can only be ordered through Mazda eStore. • In an effort to achieve a higher level of Customer Experience and retain the value of Mazda’s vehicles, MNAO Warranty Operations is allowing all Mazda dealers to utilize a third party, SPECMO Enterprises, Inc., for Instrument Panel Cluster (IPC) odometer setting service. With the use of SPECMO’s services, it is possible that the odometer will be set between 10 to 31 miles over the odometer mileage at the time of replacement for both warranty and customer pay repairs. Please make sure that the customer is aware that there may be a slight variance to the odometer, in which case the customer may have to accept the slightly higher mileage. Since odometer setting service is not part of the warranty repair, it is not warrantable nor required, but optional. However, Mazda Warranty policy provides after- warranty assistance (AWA) or DSA that can be utilized to cover this service expense.
SA-059-192019-12-21. Service bulletin. SEATS; ELECTRICAL SYSTEM. Some customers may complain that the seat warmer turns off after 10 minutes in manual mode and will not turn back on until the vehicle is restarted. DTC B1030:13 (Seat warmer unit (LH) circuit malfunction (heater side)) may also be stored. This may be caused by a faulty seat warmer control unit (A).
SA-032-192019-12-20. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM; STRUCTURE; EQUIPMENT ADAPTIVE/MOBILITY. When replacing the Body Control Module (BCM) in a 2019 Mazda3, it needs to be configured and the instructions in the Workshop manual on MGSS are incorrect. Use the instructions in the Repair Procedure below to configure the new BCM.
SA-039-19a2019-11-24. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; EQUIPMENT ADAPTIVE/MOBILITY. During BCM replacement, MDARS may display a Configuration Error warning message. This may be caused by any of the following: • Poor internet connection • MDARS failure • Low Battery Perform the BCM Recovery Procedure below to manually configure the BCM.
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.
MSP272019-11-21. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; STRUCTURE:BODY:HATCHBACK/LIFTGATE:HINGE AND ATTACHMENTS; LATCHES/LOCKS/LINKAGES:DOORS:LATCH; EQUIPMENT. Mazda Motor Corporation has decided to conduct a Mazda Service Program (MSP) on certain 2019 Mazda3 5HB vehicles produced from November 6, 2018 through May 28, 2019. Concern Outline: On certain subject Mazda3 5HB vehicles with the advanced keyless function, all doors, fuel filler door, and the liftgate can be locked by pressing the door-lock switch on the liftgate. If the liftgate door-lock switch is pressed with the transmitter/key left inside the vehicle, all doors will lock and cannot be unlocked from the outside. The liftgate can be unlocked using the liftgate opener because of the lock-in prevention function. This was the original design of the vehicle with advanced keyless function, but the original design does not match customer’s expectation. It is difficult to retrieve the keys inside the vehicle through the liftgate especially if the rear seats are blocked (with two child seats, luggage etc.). Action Required: Reprogram the body control module (BCM) and low-frequency control unit (LFU) with M-MDS using Mazda Diagnostic and Repair Software (MDARS) for all affected Mazda3 5HB vehicles in dealer inventory, and when customers bring their vehicles for maintenance, or other service/warranty work. The subject vehicles should not be delivered to customers until the repair of MSP56 is completed. Please inform the customer that the BCM and LFU will be reprogrammed to the modified calibration, free of charge. The modified calibration prevents the vehicle from being locked if the keys are still inside. The dealer inventory list will be posted to MGSS by the end of today. Inventory vehicles sold with MSP56 in open status will have any PDI New Car Ready claim debited.
SA-046-192019-11-21. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. On the 2019 Mazda3 (BP) and and all 2020 Mazda vehicles (except CX-3), the CR2032 button cell battery is required for the new type remote transmitter. If it is mistakenly replaced with the conventional CR2025 used in the previous type remote transmitter, it may cause a malfunction. Verify the button cell battery type before replacing it.
01-018-19-36422019-11-21. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. Some vehicles that have a drained battery recovered may exhibit that the engine will not start and the ignition switch will not turn off. The following DTC's may also be stored: • U3000:49 - BCM internal malfunction • B10E7:12 - IG1 relay circuit malfunction • P0615:11 - Starter relay circuit malfunction. This concern most likely occurs on vehicles in a show room with frequent door operation and poor battery maintenance. For proper battery maintenance of show room vehicles, refer to SA-043/19.
SA-019-192019-11-21. Service bulletin. EQUIPMENT; FORWARD COLLISION AVOIDANCE: SENSING SYSTEM: RADAR; ELECTRICAL SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. Some vehicles may experience M-MDS (MDARS) showing the front radar dynamic aiming is incomplete, although the procedure is completed. This is caused by faulty front radar software logic and a mass production change is planned. If the screen below is displayed after the front radar dynamic aiming is performed, check the vehicle using the following inspection procedure.
07-007-19-36382019-11-21. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM; ENGINE. Some customers may complain about poor heater performance even after the engine reaches normal operating temperature. This may be caused by a plugged heater core. For 2014-2016 Mazda6 and 2013-2016 (US spec) / 2017 (Mexico spec) CX-5, the CHECK ENGINE light may turn on with DTC P011A:00 (ECT sensor No.1/No.2 performance problem) stored at the same time. NOTE: Refer to TSB 01-015/15 if the customer is using a block heater at temperatures below freezing. To solve this concern, two mass production changes have been implemented. a) The concentration of the coolant has been increased so that the amount of the contained anti-rust additive is higher. b) The composition of the coolant has been changed (the ratio of the anti-rust additive has increased).
SA-045-192019-11-01. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. Currently, Mazda does not have a way to cut the auxiliary keys for the new style remote transmitter as they use a different key code than the previous transmitter key. Follow the repair procedure if one or both auxiliary keys are lost:
SA-044-192019-10-30. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. The "FORCED IGNITION ON PROCEDURE" was made available to dealers through this service alert.
SA-043-192019-10-30. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. On 7th generation vehicle (2019-2020 Mazda3 (BP) and 2020 CX-30 (DM)), when the door is opened/closed with the ignition switch off, the battery current is approximately 7A, which is three times larger than previous generation models (2.5A on Mazda6 (GL)). In addition, after the door is closed, a 6A current continues for 6 minutes on 7th generation vehicles. This is why frequent door operation in the show room may result in low battery voltage.To avoid a drained battery, especially when the vehicle is displayed for customers in a show room (with door operation being more frequent and battery consumption being larger), it is highly recommended to perform more frequent battery maintenance than for previous generation models.
09-037-19-36362019-10-30. Service bulletin. ELECTRICAL SYSTEM; FUEL SYSTEM, GASOLINE; EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT. Some customers may experience one or both of the following: The “Next Service Date” setting under Vehicle Status Monitor in the center display changes to “Manual” by itself after being set to “Automatic” and even with the “Manual” setting in the display, the internal calculation works as if set to “Automatic”. The “Engine oil change” message is then displayed when the oil deterioration level reaches the threshold. This is caused by a communication error between the PCM, BCM and CMU. The average fuel economy display in the instrument cluster gradually gets worse after 1,200 miles (2,000 km) of driving without a reset regardless of the actual driving situation. This concern is only present in the display and not in the actual fuel consumption. To correct these issues, the software of the BCM has been modified.
SA-042-192019-10-04. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. Customers having MAZDA CONNECT concerns should have their vehicle repaired using the following repair procedure. NOTE: Before proceeding: Confirm that the Connectivity Master Unit (CMU) is updated to the latest software version. Go to MGSS - Infotainment - MAZDA CONNECT Updates, Confirm that the customers device is updated to the latest software version. Apple Carplay/Android Auto FAQ, go to SA-001/19.
09-035-19-36372019-10-04. Service bulletin. LATCHES/LOCKS/LINKAGES; ELECTRICAL SYSTEM. If the body control module (BCM) or the LF control unit (LFU) has been replaced and configuration has been performed, communication between the BCM and the LFU may not work properly due to a difference of the software level. Symptoms: If the BCM has been replaced: Without a remote transmitter - the door lock switch at the liftgate will not lock doors, With a remote transmitter - the door lock switch at the liftgate will lock the doors even when the front or rear door(s) are opened, If the LFU has been replaced: Without a remote transmitter - the door lock switch at the liftgate will lock the doors with the answer back sound.
SA-010-19j2019-09-23. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; VISIBILITY; EQUIPMENT; ELECTRICAL SYSTEM; LANE DEPARTURE: BLIND SPOT DETECTION; WHEELS. 2019-2020 MAZDA3 SERVICE CAUTIONS FOR NEW AND REVISED FEATURES. The 2019-2020 Mazda3 has new and revised features that are different from previous models, and may be difficult to understand. This Service Alert provides valuable information to support potential dealer and customer concerns. Index: PDI fuse, Apple CarPlay / Android Auto Install Kit, Blind Spot Monitoring System (BSM), Front Wiper Service Caution, i-ACTIVSENSE Switch, Traffic Sign Recognition (TSR), MAZDA CONNECT Power Function, MAZDA CONNECT Center Display View, In-Vehicle Digital Owner's Manual, Navigation System, SIRIUSXM Data Service, Power Door Locks, Auxiliary Key, Transmitter Battery Saving Function, Keyless Entry Using Auxiliary Key, Rear Door Child Safety Locks Operation, Link Seat & Climate Control Temperatures, Seat Warmer Turns OFF, Electric Parking Brake (EPB), A/C Air Temperature Is Not Cold, Tire Pressure Monitoring System (TPMS), Condition Based Maintenance, M-MDS (MDARS), Part Replacement.

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