Navigation System Symptom Troubleshooting - Interface dial buttons do not work
  1. Check for continuity between navigation unit connector B (32P) terminals No. 23 and No. 25.
Is there continuity?
YES -
There is a short in the wire. Replace the affected shielded harness.
NO -
Go to Step 9 .
  1. Substitute a known-good interface dial, and recheck.
Is the system OK?
YES -
Replace the original interface dial. ■
NO -
Replace the navigation unit. ■