On Tuesday 22 May 2007, FGW commence an active test of its Selective Door Opening (SDO) system forming a special empty HST from Plymouth to Penzance and return. This will enable FGW and the RSSB to view the system operationally in a genuine environment, and ascertain whether the work carried out by FGWs Safety and Engineering teams has been sufficient. After the test, the system will be disarmed, and work will continue towards introduction across the fleet later this year.

In a news letter sent out by FGW Managing Director to her staff she said "The SDO system has enormous safety benefits. It prevents doors being unlocked at stations where shorter platforms mean the whole train cannot be accommodated, and will allow HSTs to stop at stations which are currently prohibited.

The modified set is due to form the following train on Tuesday 22 May

5Z30
LAIRA TMD 11:00
MTGOULDJN 11:05 11:12
LIPSON JN PASS 11:15
PLYMOUTH 11:18 11:21
STBUDFREJ PASS 11:27
SALTASH 11:31 11:33
STGERMANS 11:38 11:44
LISKEARD 11:54 11:56
ST PINNCK PASS 12:01
LARGIN PASS 12:02
BODMINPKW 12:06 12:08
LOSWITHEL 12:12 12:17
PAR 12:23 12:25
STAUSTELL 12:31 12:33
BURNGLWJN PASS 12:36
PROBUS PASS 12:43
TRURO 12:49 12:51
PENWTHRSJ PASS 12:53
BALDHU PASS 12:56
REDRUTH 13:02 13:04
CAMBORNE 13:09 13:11
HAYLE 13:18 13:23
ST ERTH 13:26 13:28
LONG ROCK PASS 13:36
PENZANCE 13:39

5Z31
PENZANCE 14:32
LONG ROCK PASS 14:37
ST ERTH 14:41 14:43
CAMBORNE PASS 14:52
REDRUTH PASS 14:56
TRURO 15:06 15:08
PROBUS PASS 15:14
BURNGLWJN PASS 15:21
STAUSTELL 15:23 15:25
PAR PASS 15:31
LOSWITHEL PASS 15:36
BODMINPKW PASS 15:39
LARGIN PASS 15:44
ST PINNCK PASS 15:4
LISKEARD PASS 15:4
STGERMANS PASS 15:5
SALTASH 16:05 16:1
STBUDFREJ PASS 16:1
PLYMOUTH 16:20 16:2
LIPSON JN PASS 16:3
MTGOULDJN 16:34 16:4
LAIRA TMD 17:01