DTC U0301 (1.5 L Engine)

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DTC U0301: PGM-FI System and Transmission System Program Version Mismatch

General Description

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

The controller area network (CAN) uses two signal lines. H line and L line, and it receives and transmits multiple signals simultaneously to/from multiple control modules. When the software version in the powertrain control module (PCM) and the transmission control module (TCM) are mismatched for a set time, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type

Execution	Continuous
Sequence	None
Duration	1 second or more
DTC Type	One drive cycle, MIL on

Enable Conditions

Condition
Vehicle	ON mode

Malfunction Threshold

The software version in the PCM and the TCM are mismatched for at least 1 second.

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.

PCM software data not updated

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected, the MIL comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory.

Conditions for clearing the DTC

The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.