DTC Troubleshooting: U0104 (107)
DTC U0104:
 F-CAN Malfunction (PCM-ACC Unit)
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review General Troubleshooting Information.
  1. Turn the ignition switch to ON (II).
  1. Clear the DTC with the HDS.
  1. Check for Temporary DTCs or DTCs in the PGM-FI SYSTEM with the HDS.
Is DTC U0104 indicated in the PGM-FI SYSTEM?
YES -
Go to the DTC U0104 troubleshooting in the PGM-FI SYSTEM. ■
NO -
Go to Step 4 .
  1. Check for Temporary DTCs or DTCs in the A/T SYSTEM with the HDS.
Is DTC U0104 indicated in the A/T SYSTEM?
YES -
Go to Step 5 .
NO -
Intermittent failure, the system is OK at this time. If any other Temporary DTCs or DTCs were indicated, go to the indicated DTC's troubleshooting.■
  1. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
  1. Start the engine, and wait for at least 2 minutes.
  1. Check for Temporary DTCs or DTCs in the A/T SYSTEM with the HDS.
Is DTC U0104 indicated in the A/T SYSTEM?
YES -
Check for poor connections or loose terminals between the ACC control module and the PCM. If the PCM was updated, substitute a known-good PCM, then go to Step 6 . If the PCM was substituted, go to Step 1 .
NO -
Go to Step 8 .
  1. Monitor the OBD STATUS for U0104 in the DTCs MENU with the HDS.
Does the HDS indicate PASSED?
YES -
If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. If any other Temporary DTCs or DTCs were indicated in Step 7 , go to the indicated DTC's troubleshooting.■
NO -
If the HDS indicates FAILED, check for poor connections or loose terminals between the ACC control module and the PCM. If the PCM was updated, substitute a known-good PCM, then go to Step 6 . If the PCM was substituted, go to Step 1 . If the HDS indicates NOT COMPLETED, go to Step 6 .