P0203

Diagnostic Chart:

Schematic:

The Powertrain Control Module (PCM) has four injector driver circuits, each of which controls an injector. The PCM monitors the current in each driver circuit by measuring a voltage drop through a fixed resistor and is able to control the driver circuit. The current through each driver can rise to a peak of 4 amps to quickly open the injectors and can reduce to 1 amp to hold the injectors open. This is called peak and hold. If the current cannot reach a 4 amp peak, a DTC is set. This DTC is also set if an injector driver is shorted to voltage.

DTC PARAMETERS
^ Injector current is less than 4 amps.
^ Battery voltage is greater than 9 volts.
^ Above conditions met for 7 seconds.

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

DIAGNOSTIC AIDS
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 - 12-13 ohms.