Service bulletin 01-021-19-3649

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
Type	Service bulletin
NHTSA id	10169536
Published by NHTSA	2019-12-20
Manufacturer's number	01-021-19-3649
Manufacturer's date	2019-12-13
NHTSA component	POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); ENGINE AND ENGINE COOLING

NHTSA's summary

Some customers may experience the CHECK ENGINE light ON with DTC P0012:00 (Electric variable valve timing control system: Over-retarded) stored in PCM memory. NOTE: This concern occurs only on the vehicles with PCMs manufactured by MITSUBISHI.This is caused by improper control logic of the PCM detecting a false error. To correct this issue, the PCM software has been modified. NOTE: The VVT actuator is damaged by the improper control logic.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine, Transmission and driveline, Automatic transmission, Transmission control module

Trouble codes named

P0012

Vehicles listed
MAZDA MAZDA3	2019, 2020

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
19V497000	2019-06-27. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); ENGINE

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
SA-038-22	2022-07-06. Service bulletin. Service part Automatic Transaxles (ATX) manufactured on or after July, 2018 are shipped with a blank TCM that requires configuration.
SA-023-21	2021-04-06. Service bulletin. Some customers may complain about any of the following: Warning light, Warning message, Headlight(s) inoperative, Cannot shift out of Park, Many DTC's stored, Module communication errors
07-006-20-3758	2021-01-05. Service bulletin. Some customers may complain that after accelerating in hot weather, the A/C blows warm air for a longer time than other models. This is caused by improper control software of the PCM not allowing the A/C compressor to resume properly after acceleration. To eliminate this concern, the control software of the PCM has been modified.
05-002-20-3704b	2021-01-05. Service bulletin. Some customers may complain about a surging at low speeds and during acceleration. This surging is in the longitudinal direction, felt about 2 cycles per second, and occurs in the locked up 1st gear. This may be caused by the torque fluctuation and the torsional resonance in the torque converter. To correct this concern, the PCM software has been modified to reduce the torque fluctuation.
SA-065-20	2020-10-05. Service bulletin. Some customer's may complain that the HVAC system only blows warm to cool air (not cold) after starting the vehicle and not moving right away. This may be caused by a closed Active Air Shutter (AAS). Under specific circumstances, the AAS has a “learning issue” where AAS is kept closed after startup even if the PCM requests it to be open. The shutters will open and work correctly as soon as the vehicle speed exceeds 6.25 MPH (10 KPH). NO DTC will be set when this happens.
01-004-20-3684b	2020-08-04. Service bulletin. Some customers may experience the master warning light turning on and a lack of power with DTC P2BF6:00 (Exhaust shutter valve position sensor circuit low input (1DC)) stored in memory. This is caused by improper logic written in the PCM for the exhaust shutter valve position sensor.
01-004-20-3684a	2020-07-02. Service bulletin. Some customers may experience the master warning light turning on and a lack of power with DTC P2BF6:00 (Exhaust shutter valve position sensor circuit low input (1DC)) stored in memory. The PCM software has been modified to avoid the unnecessary warning light illumination and power restriction with no modification to the cylinder deactivation function and the error detection logic has been changed not to detect false error under low voltage during cranking.