Drive Signal From A/T Gear Selector

When the selector lever on a car with automatic transmission is moved to any position except P or N, current (B+ circuit) is applied to pin 14 of the Trionic control module. The control module is then programmed for automatic transmission and opens the idle air control valve slightly wider to compensate for the increase in load. Pin 14 is not used on cars with a manual gearbox.
If a gear position other than P or N is selected, the ignition timing will also be temporarily retarded, depending on throttle position, in order to protect the automatic transmission.

Brakes
If the brake pedal and accelerator are both depressed and engine speed is below 3000 rpm, the ignition will be retarded. The purpose of this is to protect the transmission if the engine stalls.