Based on information from various sensors, the PCM measures the fuel injection amount. The fuel injector is a solenoid-operated valve and the fuel injection amount is controlled by length of time the fuel injector is held open. The PCM controls each injector by grounding the control circuit. When the PCM energizes the injector by grounding the control circuit, the circuit voltage should be low (theoretically 0V) and the fuel is injected. When the PCM de-energizes the injector by opening the control circuit, the fuel injector is closed and circuit voltage should momentarily peak.
If there is Open in injector #5 circuit, PCM sets DTC P0205.
Item
Detecting Condition
Possible Cause
DTC Strategy
Circuit continuity check, open
Poor connection
Open or short to ground in power circuit
Open in control circuit
Injector
Enable Conditions
-
Threshold value
Open
Diagnosis Time
5 sec
MIL On Condition
2 driving cycle
Coil resistance(?)
13.8 ~ 15.2 [20?(68?)]
Fig.1) Normal waveforms of Injector under idle condition.
When the PCM energizes the injector by grounding control circuit, the circuit voltage should be low (theoretically 0V) and the fuel is injected. When the PCM de-energizes the injector by opening control circuit, the fuel injector is closed and circuit voltage should be peak at a moment.