Caution / Notice / Hint

HINT: 

• DTC P1604
  • In contrast to normal malfunction diagnosis for components, circuits and systems, DTC P1604 is used to determine the malfunctioning area from the problem symptoms and freeze frame data when the user mentions problems such as starting difficulty.

    As these DTCs can be stored as a result of certain user actions, even if these DTCs are output, if the customer makes no mention of problems, clear these DTCs without performing any troubleshooting and return the vehicle to the customer.

  • If any DTCs other than P1604 are output, troubleshoot those DTCs first.
  • Since DTC P1604 is different from other DTCs, the following procedure is shown as a reference.
• DATA LIST / FREEZE FRAME DATA
  • Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
  • When confirming the freeze frame data, be sure to check all 5 sets of freeze frame data.

    Refer to FREEZE FRAME DATA [11/2016 - ]

  • When confirming freeze frame data, if there are multiple items related to the cause of the malfunction, perform troubleshooting for all related items.
  • Try to start the vehicle under the conditions recorded in the freeze frame data which were present when the malfunction occurred. Confirm the data at this time and compare it with the freeze frame data.
  • If the malfunction does not reoccur, carefully check the vehicle conditions from when the malfunction occurred using freeze frame data.
• PRECAUTIONS
  • When performing inspections, jiggle the relevant wire harnesses and connectors in an attempt to reproduce malfunctions that do not always occur.