C2543 Diagnostic Trouble Code

C2543 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 C2543 diagnostic trouble code may include:

The engine oil will exhibit dilution from the ECUs attempts to increase engine temperature. Some vehicles advance the fuel injection timing slightly after top center to afterburn a small amount of fuel to increase exhaust temperatures. Some of this fuel enters the crankcase. When the ECU determines the necessity to regenerate the DPF, the service life of the oil be shortened significantly
Faulty or damaged wiring
Hesitation upon acceleration
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.
Defective ECU strategies or components will prevent proper regeneration

Repair Processes :

If you find a related TSB, the information will often help in diagnosing the code in question as TSBs are crested from many thousands of repairs. 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. Oxygen sensors signal the engine management computer the amount of oxygen present in the exhaust, which is used in determining and controlling the fuel ratio.

Process Tips

Diagnostic trouble code C2543 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 C2543.

Fortunately, C2543 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C2543 Trouble Code For Specific Cars

C2543 Alfa Romeo 8c Accelerometer Rear Circuit Failure
C2543 Sunbeam-talbot Tiger Memory #1 output Short to Ground
C2543 Holden Hj Power Door Memory Lock Relay Circuit Short To Battery
C2543 Koenig C Servo Motor Potentiometer Airintake Right Circuit Short To Ground
C2543 Mitsubishi Space Runner Aux Heater Overheat Sensor Circuit Short to Ground
C2543 Skoda 450 Keyless Entry Circuit Short To Ground
C2543 Mercedes Slk Air Bag Crash Sensors #1 / #2 Circuit Short To Ground