Pumpdown doesn't seem to work LCMS

I vented the system in order to clean the spray chamber, nebuliser, and transfer ion capillary. After completion, I started a pump down sequence and left the system over the weekend. The rough vacuum is at ~2.6 torr and the high vacuum is 0.005 mtorr. According to the help section on chemstation the rough should be 1.5 to 2.5 torr and the high < 10-5 torr. Turbo 1 is operating at 100%, 141.1 W, but turbo 2 is 0% and 0 W. 


I vented the system again, left the MSD off but restarted the LC which was running fine. But when the system is started with the MSD on, all modules show red lights and have shutdown failures. 


Should turbo 2 be coming on during the pumpdown process? Could this be due to/causing the rough and high vacuum to not be at the values they should be?


Our system is just over a year old, its a single quad LC/MSD and rarely gets used (sits in standby mode most of the time). This was the second occasion it has been vented.

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