Fault code lookup

PowertrainP1821

Caution

Severity: Caution - get it checked when you can

Short circuit to negative

20 brands affected · Description from BMW 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 20

BrandCodeDescriptionSystem
BMWP1821Short circuit to negative BrandPowertrain
CheryP1821Clutch slip too large at 1st gear BrandPowertrain
DaewooP1821Transmission Transfer Case Clockwise Shift Relay Coil Open Circuit BrandPowertrain
EOBDP1821Koblingssystemfejl BrandPowertrain
GMP1821Internal mode switch B circuit low voltage BrandPowertrain
HoldenP1821Clutch Temperature Sensor BrandPowertrain
HyundaiP1821No description available Powertrain
IsuzuP1821No description available Powertrain
Land RoverP1821Combustion air fan circuit defective BrandPowertrain
MahindraP1821No description available Powertrain
MitsubishiP1821Shift fork POS. sensor1 high BrandPowertrain
OpelP1821Internal mode switch B circuit low voltage BrandPowertrain
PeugeotP1821No description available Powertrain
PorscheP1821Drucksensor D Kurzschluss nach Plus oder Unterbrechung BrandPowertrain
ProtonP1821Shift fork POS. sensor1 high BrandPowertrain
SaabP1821Internal mode switch B circuit low voltage BrandPowertrain
MG (SAIC)P1821Clutch Temperature Sensor Circuit Short to Ground BrandPowertrain
SuzukiP1821Clutch system malfunction BrandPowertrain
TataP1821No description available Powertrain
ToyotaP1821Transfer case clockwise shift relay coil circuit open 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 3

These 7-character codes are manufacturer-specific variants of P1821 and may be reported by some scan tools.

BrandCodeDescriptionSystem
Mercedes-BenzP182100No description available Powertrain
SprinterP182100No description available Powertrain
SsangYongP182100Open or short to battery in magnetic clutch coil circuit BrandPowertrain

6Related codes

Browse Pxxx codes or P182xx codes.

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