Toyota Repair: 1994 sr5 pickup a/c, sr5 v6, jumper wire

Question
doing a 134a conversion on my 1994 sr5 v6 4wd pickup as the a/c quit blowing cold and r12 unavailable. evacuated r12, replaced dryer,and evacuated system w/ vacuum pump. need to know how to jump low pressure safety switch and  start compressor for recharge. familiar with american cars but have checked 3 service manuals and can find nothing on the safety switches (if they even exist) believe the compressor to be good just not engaging clutch because of switch. thanks for the help!

Answer
On this model there is no low pressure switch there is only a high side switch and it is located inside on the evaporator, you can apply 12 volts directly to the compressor clutch, disconnect the connector for the cluch and put 12 volts directly from the battery with a jumper wire to the clutch but you still need to repair the cause for the compressor not turning on normally.