DTC Advanced Diagnostics: P049F (3.0L Engine)

DTC P049F: Left Active Exhaust System Electrical Failure

General Description

Courtesy of HONDA, U.S.A., INC.

The left active exhaust actuator runs a self-diagnostic function to monitor if there is electrically or mechanically failure. The powertrain control module (PCM) communicates with the left active exhaust actuator via local interconnect network (LIN) line and detects failure by monitoring the self-diagnostic information. If the received self-diagnostic information from the left active exhaust actuator is abnormal, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type

Execution	Continuous
Sequence	None
Duration	45 seconds or more
DTC Type	Two drive cycles, MIL off

Enable Conditions

Condition
Vehicle	ON mode
Other	LIN communication is OK
Other	Active exhaust actuator calibration is completed or failed

Malfunction Threshold

The received self-diagnostic information from the left active exhaust actuator is abnormal for at least 45 seconds.

Possible Cause

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Left active exhaust actuator power supply voltage low
Left active exhaust actuator power supply voltage high
Left active exhaust actuator failure

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, a Confirmed DTC, the freeze data, and the on-board snapshot are stored. The MIL does not come on.

Conditions for clearing the DTC

The Pending DTC, the Confirmed DTC, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.