T11-5 (IND) - T11-9 (GND) LG - W-B Tire pressure warning light
signal Ignition switch on ......... Looks like pin 5 is the power signal for the TPWL on the combination meter. A simple inline on/off switch should do the trick.
Disconnecting the TPS ECU is not going to work. There is some simple logic that detects if there is no connection. It will send DTC's to the ECU and might trigger a MIL.