HomeP0126 · Code meaning and manufacturer information
Powertrain

P0126

Code meaning and manufacturer information

P0126

What does this code mean?

The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.

A code identifies a detected condition, not a part that must automatically be replaced.

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A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.

Manufacturer communications

6

Original wording in English

DRW59 Warr a

MAZDA

Reported code forms P0126:00

Subject: Notification of Dealer Re-Work (DRW59) – 2026MY CX-30 and 2026MY Mazda3 - Check Engine Light On With DTC P0126:00 Dear Mazda Dealer Colleagues, Mazda Motor Corporation has decided to conduct a Dealer Re-Work on…

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DRW59 Warranty

MAZDA

Reported code forms P0126:00

Subject: Notification of Dealer Re-Work (DRW59) – 2026MY CX-30 and 2026MY Mazda3 - Check Engine Light On With DTC P0126:00 Dear Mazda Dealer Colleagues, Mazda Motor Corporation has decided to conduct a Dealer Re-Work on…

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DRW59 Repair

MAZDA

Reported code forms P0126:00

Subject: Notification of Dealer Re-Work (DRW59) – 2026MY CX-30 and 2026MY Mazda3 - Check Engine Light On With DTC P0126:00 Dear Mazda Dealer Colleagues, Mazda Motor Corporation has decided to conduct a Dealer Re-Work on…

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DRW59 Dlr Ltr

MAZDA

Reported code forms P0126:00

Subject: Notification of Dealer Re-Work (DRW59) – 2026MY CX-30 and 2026MY Mazda3 - Check Engine Light On With DTC P0126:00 Dear Mazda Dealer Colleagues, Mazda Motor Corporation has decided to conduct a Dealer Re-Work on…

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01-006-26

MAZDA

Reported code forms P0126:00

Some customers may experience the check engine light on with DTC P0126:00 (Thermostat stuck open) stored. This is due to improper PCM logic control. To eliminate the concern, the PCM control software has been modified.…

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SA-062-25

MAZDA

Reported code forms P0126:00

Some vehicles equipped with a countermeasure Coolant Control Valve (plug in place of the thermostat inside the CCV) may experience a DTC P0126:00.

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Check vehicle applicability

1

A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.

MakeModelModel year
MazdaMAZDA32026

Before replacing a part

Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.

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Can I keep driving?

A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.