Description of On-Board Diagnostics

1. With the ignition switch in the OFF position simultaneously press the C/T and STEP buttons and hold.
2. Turn ignition switch ON, then release C/T and STEP buttons.
3. OTIS lights all segments on the VFD for 2-4 seconds. Check for segments that are not illuminated.
4. If OTIS displays PASS, the module is OK.
5. If OTIS displays FAIL, replace the module.
6. If OTIS displays BUS, check for an open or a short in the PCI bus communication wire.
7. Press the C/T or the STEP button to exit self-test.