Circuit Description
The ECM enables an injector on the intake stroke of each cylinder by grounding
the control circuit through an internal switch. When the ECM is commanding an injector
on, the voltage of the control circuit should be near 0 volts.
When the injector is not being used, the voltage on the control circuit should be
near battery voltage. If the ECM does not get a response from the injector, it will
set this code. The ECM will continue to test the circuit and if the fault goes away,
the driver will be reactivated.
DTC Parameters
DTC P0201 will set when the injector circuit is open and the following conditions
exist:
| • | Battery voltage is between 7.5 and 15 volts |
P0201 is a (type B) DTC.
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 together.
| • | Fuel in the oil is a good indication of a leaking injector |
| • | Each injector is supplied battery voltage with the ignition On |
| • | Injector resistance = 14 - 23 ohms |
