Radiator Fan Circuit Troubleshooting
  1. Check for continuity between under-hood fuse/relay box connector B1 and body ground.
Is there continuity?
YES -
Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom goes away with a known-good ECM/PCM, replace the original ECM/PCM. ■
NO -
Repair open in the wire between the under-hood fuse/relay box and body ground. If the wire is OK, check for a poor ground at G301.■