Fault code lookup

PowertrainP21C7

Caution

Severity: Caution - get it checked when you can

Reductant control module power relay/relays control circuit/open

7 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 7

BrandCodeDescriptionSystem
Ashok Leyland CVP21C7Safety Restraint System. Sensor N. Loss Or Error In Messages BrandPowertrain
EOBDP21C7Reductant vezérlőmodul relé/relék vezérlőkör/nyitott BrandPowertrain
IsuzuP21C7No description available Powertrain
Land RoverP21C7Reductant Control Module Power Relay/Relays Control Circuit/Open BrandPowertrain
SuzukiP21C7Open load error of the external relay BrandPowertrain
TataP21C7No description available Powertrain
ToyotaP21C7Reductant control module power relay/relays control 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.

5Related codes

Browse Pxxx codes or P21Cxx codes.

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