Engine Management

Scan Tool 21 (MIL 27):

Trouble Code Number
- Scan tool 21
- General Scan Tool P0201
- MIL 27

Fault Message
- Injector #1 Control Circuit

Background
- Grounds for the injector circuits are provided by the PCM.
- Battery power is provided through the MFI relay (ASD relay).
- This DTC is set it an open or short-circuit condition is detected in the control circuit for the individual injector.

Range of Check
- Battery voltage: 12 V or more
- MFI relay (ASD relay): ON
- Engine: 3,000 r/min or less

Set Condition
- Counter electromotive force is not detected for 3 seconds immediately after injectors turn off.

Probable Cause
- Open or shorted injector control circuit
- Open injector
- Open MFI (ASD) voltage supply at injector
- Driver in PCM failed