P0203

Diagnostic Chart:

Wiring Diagram:

The injector system on both SOHC and DOHC engines utilize sequential fuel injection (SFI). The PCM independently controls each fuel injector through a driver circuit, in accordance with intake valve opening. The driver circuit is internally located in the PCM providing the ground for each injector. The length and time an injector is held open (grounded by PCM) is calculated based on engine speed load and valve location from the crankshaft position sensor.

DTC PARAMETERS

DTC P0201 (Injector 1), or DTC P0202 (Injector 2), or DTC P0203 (Injector 3), or DTC P0204 (Injector 4) will set if:

^ An injector circuit is open, shorted to voltage or shorted to ground.

NOTE: The injector circuit is continuously checked when the engine is running.

DIAGNOSTIC AIDS

When attempting to diagnose an intermittent problem use the Scan tool to review malfunction history diagnostic information. This supplemental data can be used to duplicate a problem.

Intermittents or opens suspected to be at the connector can be detected by using a diagnostic service probe. Voltage can be read on wires without disconnecting any connectors.

Check the tightness of the female terminal grip with a spare male terminal.

An open or shorted injector circuit will cause a misfire DTC to set. Diagnose an injector code first if an injector and a misfire DTC occur.

^ Fuel in the oil is a good suspect of a leaking or grounded injector.

^ Each injector is supplied battery voltage when the key is in the On position.

^ Injector resistance - 12 ohms.