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P0203 Cylinder 3 Injector Circuit/Open

AutoHex Online Help: Hyundai TERRACAN(HP) 2005
Component Location
General Description

Injectors spray fuel in the highly compressed combustion chamber, and power generates through combustion process.

Fuel pressure is raised to 1600bar in common rail diesel engine for the purpose of making fuel into minute particles. And fuel devided into minute particles leads smoke reduction, high power generation, and improved fuel efficiency.

Needle valve inside of injector is located between A and B chamber. If applied pressure to B chamber is relived by injector solenoid, niddle valve is raised by the pressure of A chamber then, fuel is injected. If same pressure is applied to A and B chamber, niddle valve closes by the elastic force of spring then, fuel injection stops.

As electronically controlled injector is applied instead of mechanical injector, it becomes possible to control pilot and post injection, injeciton duration and quantity independantly. Therefore engine performance is improved by these control.

For more precise correction of fuel injection quantity, inputting C2I data to ECM is required.

?C2I(Individual Injector Correction) : During the production process of injectors, it is inevitable for each injector to have different injection characteristic. To cope with the various fuel injection characteristic optimally, NO. which consists with 16 character is given to a certain injector. The composition of NO. corresponds to a certain specific fuel injection characteristic. The characteristic is arleady saved at ECM. Therefore, if the NO. on injectors is inputted to ECM using SCAN TOOL, optimum fuel injection is achieved.

DTC Description

P0203 is set when injector contol is impossible due to open or short in #3 injector circuit.(#3 injector is installed at #4 cylinder.)

DTC Detecting Condition


Detecting Condition

Possible Cause

Threshold Value

? Open or short in #3 cylinder injector circuit (OC/SC-/SC+)

? Injector circuit

? Injector component

Fail Safe

? Idle RPM rises to 1000RPM.

? Engine operates with 3 injectors.

? Engine noise occurs.

Check lamp


? OC (Open Circuit) : Open, SC- (Short Circuit - ) : Short to ground , SC+ (Short Circuit +) : Short to battery


Injector component resistance

Injector driving voltage

Injector driving current

Injector control type



Peak current : 18±1A

Current control

Hold-in current : 12±1A

Recharging current : 7A

Schematic Diagram
Signal Waveform