AWS TPWS Self Test 

When a train cab is energised, the Automatic Warning System (AWS) and Train Protection and Warning System (TPWS) undergoes a self test. The test is completed as follows:
- Check all lights illuminate on the TPWS panel
- Ensure AWS warning tone (horn) can be heard
- Observe AWS visual indicator is all black
- Acknowledge with AWS/TPWS acknowledge/reset button
- Ensure AWS warning tone (horn) is replaced with a clear tone (bell)
- Observe AWS visual indicator is black and yellow
- Observe all lights on TPWS panel extinguished