4000 Series
- Check battery and voltage stabilizer for proper voltage. Remove center console. Start engine. Connect Tester (VW 1301) between gauge and ground.
- With dial set to 422, gauge should read 60°. With dial set to 146, gauge should read 90°. With dial set at 53, gauge should read 120°. Keep tester connected for a minimum of one minute to allow gauge to reach checking range.