C120C Lotus Elise Diagnostic Trouble Code

C120C Lotus Elise code definition:
C120C is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code for Lotus Elise.

C120C Lotus Elise is defined as Camshaft Position Sensor A Circuit Low. This means the CMP (camshaft position) sensor circuit on engine bank 1 sends an irregular reading. There are two wires dedicated for each coil; one is battery feed which usually comes from the distribution center, and the other one for the coil driver circuit from the PCM. The PCM grounds or ungrounds the circuit to activate or deactivate the coil.

Symptoms

Symptoms of a C120C Lotus Elise diagnostic trouble code may include:

Vacuum leak on the engine
Reduction in engine performance, especially at low RPM levels
Engine surge
Rich or lean exhaust

Possible Causes :

The Mass Airflow sensor will also cause this problem. Mass Airflow circuit malfunction.
Fuel with a large percentage of sulfur will clog the DPF quickly
Rarely - faulty Powertrain Control Module (PCM-programming required after replacement)

Common Misdiagnoses

Exhaust Gas Recirculation System Valve 1 Problem
BBV Sensor Circuit Low Voltage Problem
Transmission Engaged At High Throttle Angle Problem
Cruise Inhibit Control Circuit Problem
TFP Valve Position Switch-Drive Without Drive Ratio Problem

Repair Processes :

Look for damage to the tank indicating impact that may have damaged the fuel pump or sender. If all testing has passed so far yet you still have the same code, check your scan tool and see if it can open and close the IMRC valve.

Process Tips

Diagnostic trouble code C120C Lotus Elise 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 C120C Lotus Elise.

Fortunately, C120C Lotus Elise is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.