C2181 Diagnostic Trouble Code

C2181 is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a C2181 diagnostic trouble code may include:

Engine surge
Blown fuse (if applicable)
Lack of power
Rich or lean exhaust

Possible Causes :

Faulty IMRC actuator relay (if equipped)
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Rarely - faulty Powertrain Control Module (PCM-programming required after replacement)

Repair Processes :

It should be pretty close to battery voltage (12 volts). If not, then this is the circuit that has the problem. With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. Replace the oxygen sensor that is downstream from the catalytic converter on the side of the engine that does not contain cylinder #1. Also, if a oxygen sensor code stating "heater circuit malfunction" the sensor has most probably failed.

Process Tips

Diagnostic trouble code C2181 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before C2181.

Fortunately, C2181 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C2181 Trouble Code For Specific Cars

C2181 Ariel Atom Air Suspension LR Air Spring/Shock Solenoid Output Circuit Short To Ground
C2181 Monteverdi Sahara Battery Power Supply ECU Circuit Short To Ground
C2181 Porsche Boxster Fuel Pressure Regulator 1 Control Circuit
C2181 Jordan A Seat Front Up/Down Potentiometer Feedback Circuit Short To Ground
C2181 Ford Versailles Module Supply Voltage Out Of Range
C2181 Fiat X1 Left Rear Backup Lamp Circuit Failure
C2181 Ford Aero LF LAMP HIGH BEAM CIRCUIT Short to Battery