TPIS - Tire Pressure Indicating System.
It's an option on the 744 and I think standard on the 777 as CX chooses to have the bare minimum on their 400's, (No Auto-start, No taxi light just turn-offs, No PVD, No Headrests, No Full face Oxy, No Therapeutic Oxy, No lower Weather radar they have a torch, No Elec Driven Hyd pumps on 2 & 3, No TPIS, No Doors Auto/Man Indication even though the system is fitted when the A/C is built the wires just aren't hooked up, Plus the bare minimum on the PFD, ND and EICAS).
[This message has been edited by CCA (edited 05 October 2000).]