Fault code lookup

PowertrainP1AC1

Caution

Severity: Caution - get it checked when you can

Reduction gear position sensor

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
CheryP1AC1Engine maximum torque invalid BrandPowertrain
DaewooP1AC1No description available Powertrain
EOBDP1AC1Reductiebakpositiesensor BrandPowertrain
GMP1AC1No description available Powertrain
HoldenP1AC1Drive Motor Coolant Temperature Sensor Circuit Short to Ground BrandPowertrain
HondaP1AC1No description available Powertrain
MitsubishiP1AC1Battery cooling fan BrandPowertrain
OpelP1AC1No description available Powertrain
PeugeotP1AC1No description available Powertrain
ProtonP1AC1Battery cooling fan BrandPowertrain
SaabP1AC1No description available Powertrain
MG (SAIC)P1AC1EDU Water Temperature Sensor Short to Ground BrandPowertrain
ToyotaP1AC1Reduction gear position sensor 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.

5Related codes

Browse Pxxx codes or P1ACxx codes.

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