C2004 Diagnostic Trouble Code

C2004 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 C2004 diagnostic trouble code may include:

Faulty O2 Sensor
Lack of power
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected
Diminished fuel efficiency

Possible Causes :

A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Faulty IMRC actuator relay (if equipped)
Fuel with a large percentage of sulfur will clog the DPF quickly

Repair Processes :

Look for rubbing, scraping, bare wires, worn spots or melted plastic connectors. Pull the connectors apart and carefully look at the terminals (the metal parts) inside the connectors. 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. Look at the plug wires to make sure they are not burnt or laying on the exhaust.

Process Tips

Diagnostic trouble code C2004 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 C2004.

Fortunately, C2004 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C2004 Trouble Code For Specific Cars

C2004 Zagato Isocity SCP (J1850) Invalid or Missing Data for Traction Motor
C2004 Chrysler Sedan Exhaust Gas Recirculation Flow Malfunction
C2004 Mitsubishi Lancer Evo 9 Aux A/C Blower Speed 1 Circuit Failure
C2004 Wiesmann Gt SCP (J1850) Invalid or Missing Data for Network Control
C2004 Bmw-isetta 611 Communication Link to Display and Switch Module Error
C2004 Skoda 105 IP Power Sliding Door Open/Close switch Ckt Short to Gnd
C2004 Abarth 2200 4X4 Initialization Failure