Circuit/System Verification

WARNING: This page is about a different car, the 2017 GMC Acadia. However, it is still accessible from the selected car via links, so may be relevant.

Ignition ON.
Verify the scan tool Right Turn Signal Switch and Left Turn Signal Switch parameters change between Active and Inactive while cycling the turn signal switch between the right and left positions.
- If the parameters do not change
  Refer to Turn Signal/Multifunction Switch Malfunction.
- If the parameters change
Verify the left front turn signal lamp turns ON and OFF while commanding the Left Front Turn Signal Lamp ON and OFF with a scan tool.
- If the left front turn signal lamp does not turn ON and OFF
  Refer to Turn Signal Lamps Malfunction.
- If the left front turn signal lamp turns ON and OFF
Verify the right front turn signal lamp turns ON and OFF while commanding the Right Front Turn Signal Lamp ON and OFF with a scan tool.
- If the right front turn signal lamp does not turn ON and OFF
  Refer to Turn Signal Lamps Malfunction.
- If the right front turn signal lamp turns ON and OFF
Verify the left rear turn signal lamp turns ON and OFF while commanding the Left Rear Turn Signal/Stop Lamp ON and OFF with a scan tool.
- If the left rear turn signal lamp does not turn ON and OFF
  Refer to Turn Signal Lamps Malfunction.
- If the left rear turn signal lamp turns ON and OFF
Verify the right rear turn signal lamp turns ON and OFF while commanding the Right Rear Turn Signal/Stop Lamp ON and OFF with a scan tool.
- If the right rear turn signal lamp does not turn ON and OFF
  Refer to Turn Signal Lamps Malfunction.
- If the right rear turn signal lamp turns ON and OFF
All OK.