Based on information from various sensors, the ECM 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 ECM controls each injector by grounding the control circuit. When the ECM energizes the injector by grounding the control circuit, the circuit voltage should be low (theoretically 0V) and the fuel is injected. When the ECM de-energizes the injector by opening control circuit, the fuel injector is closed and circuit voltage should momentarily peak.
ECM sets DTC P0270 if the ECM detects that injector (Cylinder #4) control circuit is shorted to ground.
Item
Detecting Condition
Possible Cause
DTC Strategy
? Electrical check
? Open in power supply harness
? Short to ground in control harness
? Poor connection or damaged harness
? Faulty injector
Enable Conditions
? 10V < Battery voltage <16V
? Engine speed(rpm) >320
Threshold Value
? Open or short to Ground in control circuit
Diagnostic Time
? 1.5sec.
Temp.(°C)
Temp.(°F)
Resistance (?)
20
68
13.8 ~ 15.2