Fault code lookup

PowertrainP1D4B

Caution

Severity: Caution - get it checked when you can

Internal control module overrun monitoring error

13 brands affected · Description from Toyota data.

Key terms: Control module: a small computer that runs one part of the car · Powertrain: engine, transmission and emissions

1What it means in plain English

The engine or powertrain control system has stored a fault that does not have specific guidance in this database yet.

2Common causes

  1. Sensor or actuator fault
  2. Wiring or connector fault
  3. Vacuum or intake leak
  4. Fuel or ignition problem
  5. Control module fault

3Can I drive?

Caution · drive with care

Have it diagnosed promptly. If the car runs and drives normally, drive gently to a workshop. If it runs badly, stalls, overheats, loses oil pressure, or a warning light is flashing or red, stop safely and get professional help. If the code concerns the brakes, brake vacuum or brake assist, do not drive until it is checked: a hard pedal or longer stopping distance means stop.

This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.

4Brand data 13

BrandCodeDescriptionSystem
BYDP1D4BMotor phase loss fault BrandPowertrain
DaewooP1D4BNo description available Powertrain
EOBDP1D4Bİç kontrol modülü taşma izleme hatası BrandPowertrain
GMP1D4BNo description available Powertrain
HoldenP1D4B14V Power Module Output Voltage Sensor Circuit Low Voltage BrandPowertrain
HondaP1D4BNo description available Powertrain
MaseratiP1D4BInternal Control Module Overrun Monitoring Error BrandPowertrain
OpelP1D4BNo description available Powertrain
PeugeotP1D4BNo description available Powertrain
ProtonP1D4BNo description available Powertrain
SaabP1D4BNo description available Powertrain
MG (SAIC)P1D4BDCDC LV Voltage Sensor connected to Ground BrandPowertrain
ToyotaP1D4BInternal control module overrun monitoring error BrandPowertrain

Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.

5Extended variant codes 1

These 7-character codes are manufacturer-specific variants of P1D4B and may be reported by some scan tools.

BrandCodeDescriptionSystem
Mercedes-BenzP1D4B00The internal power supply of the control unit is implausible. BrandPowertrain

6Related codes

Browse Pxxx codes or P1D4xx codes.

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