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Body

B1252

Code meaning and manufacturer information

OBD-II / DTC

Reference meaning

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.

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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Manufacturer communications

14

Original wording in English

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SA-012-26d ↗

MAZDA

DESCRIPTION Some customers may experience a message "TCU Malfunction. Have the Vehicle Inspected" in the instrument cluster. Additional symptoms that may occur: Connected Vehicle One Time Passcode (OTP) may fail. Connected Vehicle Remote functions may fail. The following DTC's may be stored: B1252:87-8B:TCU - COMMUNICATION ERROR…

SA-012-26c ↗

MAZDA

This Service Alert supersedes the previously issued SA(s) listed below. The changes are noted in Red. SA-012/26 04/17/26, 03/04/26 and 02/26/2026 DESCRIPTION Some customers may experience a message "TCU Malfunction. Have the Vehicle Inspected" in the instrument cluster. Additional symptoms that may occur: Connected Vehicle One T…

SA-012-26b ↗

MAZDA

Some customers may experience a message "TCU Malfunction. Have the Vehicle Inspected" in the instrument cluster. Additional symptoms that may occur: Connected Vehicle One Time Passcode (OTP) may fail. • Connected Vehicle Remote functions may fail. • The following DTC's may be stored: B1252:87-8B:TCU - COMMUNICATION ERROR WITH CO…

SA-012-26a ↗

MAZDA

This Service Alert supersedes the previously issued SA(s) listed below. The changes are noted in Red. SA-012/26 02/26/2026 DESCRIPTION Some customers may experience a message "TCU Malfunction. Have the Vehicle Inspected" in the instrument cluster. Additional symptoms that may occur: Connected Vehicle One Time Passcode (OTP) may …

Check vehicle applicability

32

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

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MakeModelModel year
FordF-150 ↗2018
FordMUSTANG ↗2018
FordMUSTANG ↗2017
FordMUSTANG ↗2016
FordMUSTANG ↗2015
MazdaCX-30 ↗2026
MazdaCX-30 ↗2025
MazdaCX-30 ↗2024

Code meaning and manufacturer information

Original wording in English · Historical directory labels; manufacturer applicability has not been established for every entry.

Air Temperature Internal Sensor Circuit Short To Battery

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.