What this code means
P0602 may mean the PCM is detecting a programming or software-writing problem.
What the vehicle may do
- The vehicle may store the code after an incomplete PCM update.
- A warning light may be present.
- Vehicle behavior can vary depending on how the PCM responds.
Possible fault areas
- Possible PCM software writing problem.
- Possible incomplete PCM update process.
- Possible PCM-related problem.
Diagnostic path
Opening context
On this 2020 to 2025 Honda CR-V Hybrid, P0602 is a PGM-FI system code for a PCM programming error. In plain terms, the PCM may be seeing that its software writing or programming state is not right. The vehicle may set a warning light, may store the code after an incomplete update, and behavior can vary depending on how the PCM is responding. The broad fault areas here are possible PCM software writing trouble, an update process that did not complete correctly, or a possible PCM problem. Before getting into the code-specific steps, start with the basic troubleshooting approach so the preliminary checks are not skipped.
Set up the confirmation
Start the code-specific confirmation by turning the vehicle to the ON mode. That is the condition used here to confirm whether P0602 is being indicated before moving into the correction step.
Update the PCM
Next, update the PCM. The important caution during this step is simple: do not switch the vehicle out of ON mode while the PCM is being updated. If that happens, the PCM can be damaged. Also remember why this code can set in the first place: if the PCM update procedure is not completed, the PCM can determine there is an abnormality and store P0602.
Confirm the result
After the PCM update, run the confirmation again. The normal result is that DTC P0602 is not indicated. If the result is normal, the troubleshooting is complete, and the issue is treated as a PCM software writing problem.
If P0602 is still present
If the confirmation is abnormal after the PCM update, the diagnostic path points to a problem with the PCM. At that point, pause, recheck the earlier diagnostic path, make sure the update process and confirmation were performed correctly, and avoid guessing beyond what the test path supports.
Takeaway
The takeaway for P0602 is to treat it as a PCM programming-error path: start with the basic checks, confirm it in ON mode, update the PCM without interrupting the update, then verify that P0602 stays gone. If it does not, the path points back to the PCM. For more diagnostic training, visit stepdiagnostics.com.
Final check
For this code, the confirmed path is to update the PCM, keep the vehicle in ON mode during the update, and then verify that P0602 is not indicated.
For more guided automotive diagnostics, visit STEP Diagnostics.
