Chadwick OBD Trouble Code 27

Injector circuit isn't switching when it's told to (TBI)
(MPI) injector circuit #1 not switching right
(turbo) injector circuit #2 not switching right
(all 1990-) injector output driver

Fuel injection circuit control

QDM A ( Quad-driver module ) - 2nd gear circuit

quad driver module circuit

Injector output driver does not respond properly to the control signal or injector