Fault code lookup

PowertrainP21DD

Caution

Severity: Caution - get it checked when you can

Reductant heater 'A' current too low

12 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 12

BrandCodeDescriptionSystem
Ashok Leyland CVP21DDNo description available Powertrain
DaewooP21DDNo description available Powertrain
EOBDP21DDReductant heater 'A' current too low BrandPowertrain
GMP21DDNo description available Powertrain
HoldenP21DDReductant Tank Heater 1 Low Current BrandPowertrain
IsuzuP21DDNo description available Powertrain
Land RoverP21DDReductant Heater 'A' Current Too Low BrandPowertrain
MaseratiP21DDReductant Heater 1 Current Too Low BrandPowertrain
OpelP21DDNo description available Powertrain
PeugeotP21DDNo description available Powertrain
SaabP21DDNo description available Powertrain
ToyotaP21DDReductant heater 'A' current too low 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 2

These 7-character codes are manufacturer-specific variants of P21DD and may be reported by some scan tools.

BrandCodeDescriptionSystem
Mercedes-BenzP21DD006141,501,S_VP_CFB_RAG_HEAT_L_1: _ Symptom-Name: VP_CFB_RAG_HEAT_L BrandPowertrain
SprinterP21DD006141,501,S_VP_CFB_RAG_HEAT_L_1: _ Symptom-Name: VP_CFB_RAG_HEAT_L BrandPowertrain

6Related codes

Browse Pxxx codes or P21Dxx codes.

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