Yes...
For years (due to a bad ecu) I HAD the CSI wire directly to the battery through a toggle switch on the dash. I would hit the switch for a second or two till it cranked and started. This is somewhat how the FSM shows how to test the the injector to apply 12 volts to one side and ground the other.

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1991 FJ 80 Land Cruiser for fun.
1998 GS300 for the wife
1998 GS400 for me
1991 Supra SOLD
1986 4Runner 335k miles-22re EB inside.SOLD