I get a blank blue screen and a ‘TPM NO-COMM’ on the Pre-breathe screen of pre dive checks and when the 300 second counter reaches zero no Tick appears so I can not move to the next screen and complete pre dive checks

To be able to dive complete the following steps.
Abort Checks and confirm abort.
Go to DVO and scroll round to TPM and turn the TPM off.
Return to the main screen and then short push both buttons to the summary screen, short push both buttons again to the TPM graph screen (Here you will see no coloured graph bars, just a blue screen with ‘TPM OFF.
Long push both buttons PRE DIVE and this will take you to the first pre dive check screen.
Complete checks as normal, when you arrive at pre-breathe screen the screen will be blue with ‘TPM OFF’ but now when the 300 second timer reaches 0 a tick will appear and you can move on to complete the pre dive checks.
The problem is most likely caused by corrosion on the TPM 7 pin connector. Use a contact cleaning fluid or white vinegar and a soft brush to clean the TPM (Male) and Canister (Female) cable ends. Lightly grease around the metal section of the TPM (Male) end and re fit.

Further Resources

Assembly & Testing Document

Video Link: TPM Removal
Video Link: TPM Replacement
Video Link: Optocon TPM Removal
Video Link: Optocon TPM Replacement