C0101 Diagnostic Trouble Code

C0101 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 C0101 diagnostic trouble code may include:

Cherry red hot catalytic converter
Poor acceleration
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Reduction in engine performance, especially at low RPM levels

Possible Causes :

A faulty oxygen sensor. This will set a code in itself, however, a faulty oxygen sensor does not automatically condemn the sensor. The code just means that the sensor signal was not within specifications. An air leak or any of the above will cause an erroneous signal. There is a multitude of O2 codes relating to O2 performance which gives a clue to the problematic area.
Some aftermarket accessories and performance modifications
An air leak forward of the DPF will change the sensor readings resulting in the code

Repair Processes :

Look for missing ground strap or a rusty ground where the fuel tank is grounded to the frame. Check for damage to the wiring harness connector. If the scan tool has that capability, and the scan tool can operate the IMRC valves, then the problem is either resolved and a simple code clearing is all that's left or a new PCM would be called for. 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 C0101 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 C0101.

Fortunately, C0101 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C0101 Trouble Code For Specific Cars

C0101 Studebaker President Lamp Warning Relay Circuit Failure
C0101 Steyr-puch 650 Lamp Turn Signal Left Circuit Failure
C0101 Mercedes A 140 AAI Circuit Malfunction
C0101 Gaz 61 O2 Sensor Circuit Slow Response (Bank 1 Sensor 2)
C0101 Renault Megane Heated Backlite Input Circuit Open
C0101 Nissan Stagea Cruise Control/Brake Switch A Circuit High
C0101 Mitsubishi Libero Aux A/C Blower Speed 1 Circuit Short to Ground