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P1215

Schematic:




CIRCUIT DESCRIPTION
The AF ECU contains electronic devices called output driver modules. The output driver modules provide switchable outputs (control circuits) for operating solenoids, relays, telltales and other devices. Each of the outputs has an internal fault line that the AF ECU can monitor for faulted circuit conditions. Two types of outputs can be utilized. HIGH SIDE DRIVERS supply voltage on the control circuit. LOW SIDE DRIVERS supply a ground on the control circuit. Currently all monitored outputs are low side drivers. In order for the fault line to detect a failure the state of the control circuit must be opposite of the expected state. If the AF ECU is commanding an output ON, then 0 volts should be monitored by the fault line. If the AF ECU is commanding an output OFF then the voltage supplied to the controlled device should be monitored by the fault line.

This DTC is used to indicate that the AF ECU fault line has monitored a control circuit fault.

Monitored control circuits include the following:
^ The MIL Control (AF ECU) control circuit
^ The NGO Enable Output control circuit
^ The High Pressure Lock-Off solenoid control circuit
^ The Low Pressure Lock-Off solenoid control circuit

CONDITIONS FOR RUNNING THE DTC
The ignition is ON.

CONDITIONS FOR SETTING THE DTC
The AF ECU monitors a control circuit fault for at least 1 second continuously.

ACTION TAKEN WHEN THE DTC SETS
^ The AF ECU will illuminate the MIL and store the DTC as History during ONE drive trip in which the diagnostic runs and tails.
^ The AF ECU will record operating conditions at the time the DTC sets. This information will be stored as Freeze Frame data.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The Last Test Failed status will clear when the DTC runs and passes.
^ The AF ECU will turn OFF the MIL after 3 consecutive drive trips that the DTC runs and passes.
^ The History status will clear after 40 consecutive WARM-UP cycles with NO failures of ANY DTC.
^ All DTC Information can be cleared using a scan tool.
^ Interruption of Control Module (AF ECU/VCM/PCM or ECM) power or ground MAY clear DTC Information. Clearing DTC Information with this method is inconsistent and should not be performed.

DIAGNOSTIC AIDS
Fault Not Present
Fault Not Present indicates the condition that caused the DTC to set is intermittent and not currently present. Refer to Intermittent Conditions diagnostic information located in Symptoms-Computers and Control Systems. If any additional DTCs were stored, proceed to the applicable DTC table in the order stated in the Diagnostic System Check - Alternative Fuels (Computers and Control Systems). Intermittent Conditions

TEST DESCRIPTION

Steps 1-11:




Steps 12-18:




Steps 19-24:




The numbers below refer to the step numbers on the diagnostic table.
2. This step tests for proper operation of the gasoline fuel pump circuit and the lock-off relay.
3. The MIL should illuminate with the ignition ON and the engine OFF.
4. This step determines if the MIL control circuit is the cause of the fault condition.