Switches

Switches - Manual Control of Various TR Functions

Objective

Several functions of your '86/'87 Turbo Regal can be controlled manually by use of a simple On/Off 2-pole switch available from Radio Shack, NAPA, or your favorite parts store. The following are simple yet effective controls that anyone can connect on their TR or TTA. Generally, in each case the switch allows you to manually activate or deactivate a function which, if the switch is left in the Off position, will be controlled by the ECM. Connections will also require some 14 or 16 gauge wire and connectors.

TCC Lockup

Locking up the torque converter manually has been shown to improve ET's by up to .2 seconds and add 2 MPH to your trap speed in the quarter mile. By activating this switch at the starting line, fluid will travel to the converter forcing lockup once the transmission hits second gear (there is no fluid path to converter while in 1st or reverse.) Yes, this is hard on the converter and transmission, but so is racing in general.

The switch will ground the TCC circuit regardless of ECM request. To install, run a wire from a ground location to one end of the switch and run another wire from the other end of the switch to terminal F on the ALDL connector under the radio pod. (As you are looking at the ALDL connector, terminal F is at the top left.) The easiest way to do the connection is to splice into the wire behind the connector.

Remember to flip the switch to the Off position once you are through the quarter mile to avoid unnecessary lockup, wear-and-tear, etc. With the switch in the Off position, the converter will only lockup when the ECM commands it to lockup. Note that this retains the Brake pedal override.

High Speed Fan On

Additional cooling of the motor will help your car to be more consistent in the quarter mile and reduce detonation. By activating this switch while staging the car, the radiator fan will come on at high speed blowing cooler air under the hood. This is also good for around town cruising in the heat if you want to keep things nice and cool.

The switch will ground the High Speed Fan Relay regardless of engine temperature. To install, run a wire from a ground location to one end of the switch and run another wire from the other end of the switch to the Green wire with a Yellow stripe going from the High Speed relay to the temperature switch connector (which is vertically mounted on the intake manifold just to the right of the thermostat inlet.) You can splice into the wire at any point. The fan will continue to run as long as the switch is in the On position, however, if you leave the switch On when you shut the car off, the fan will continue to run in the high speed mode for approximately ten minutes.

Note

The above two switches can be incorporated into one 3-position switch with a single ground wire going to the center terminal of the switch. If your car does not have the Twilight sentinel rotary switch next to the headlight dimmer switch, you can remove the speedometer facia plate and cut out the existing hard plastic cutout through the facia plate and mount this 3-position switch here.

TCC Defeat

If your torque converter tends to lockup early (dragging down the motor) and you do not have access to EPROM programming, this switch allows you to delay that lockup. (Some transmissions will hit fourth gear very hard if the torque converter is already locked up.) To install, simply cut the purple wire going to the upper brake switch (near the top of the brake pedal arm) and splice in a switch. This tricks the TCC circuit into thinking you have applied the brakes and unlocks the torque converter.

Fuel Pump(s) Kill

This switch will provide you with both a means to disable the car from thieves and a way to crank the motor after an oil change to build oil pressure without letting the engine start. To install you must access the 12V feed wire to the pumps (it is located in a plastic loom under the chrome door sill and is tan with a white stripe in color) or the fuel pump trigger circuit (the Green/Whits stripe wire going ot terminal A of the fuel pump relay). By cutting the wire and splicing in a switch, you can kill power to the fuel pump(s) whether the car is running or not. If you have installed a relay to feed higher voltage to the pump(s), simply splice the switch into the trigger circuit. (See RELAY.TXT in the tech archives.)

Fuel Pump(s) Prime

For those of you running race gas or working on the tank, this switch provides an easy way to drain the tank without running the engine. Simply turning the key to the On position without starting the engine will only run the fuel pump(s) for about 3 seconds. Underneath the alternator are two wires with connectors at the ends. One has a green connector and is the secondary tachometer feed wire, the second has a black connector and is the fuel pump prime wire. By running a wire from this connector to the hot feed on the back off the alternator (the one covered by a black plastic cover) the fuel pump will operate at normal speed with the engine off and the key in the On position. Splice a switch into that wire for manual control. If you remove the Schrader valve from the fuel rail and place a 6 foot rubber fuel line on the end of the fuel rail you can drain out that precious race fuel into a fuel jug.

Diagnostics

By grounding Pin B (second slot or wire from top right of the ALDL connector) and turning the key to the On position, the ECM will display the currently stored diagnostics. This display is in the form of flashes of the Service Engine Soon light. The sequence of events will be that the ECM will flash code 12 (1 flash, a pause, 2 quick flashes, long pause), the next code(s) and then code 12 again. Each code is flashed 3 times and up to 5 error codes can be displayed. Code 12 will again flash when the ECM is done displaying error codes. See elsewhere in the Tech subdirectory for the list of potential error codes.

Panel

A simple switch housing panel can be made to replace the ash tray in the console. Measure the opening and cut a piece of rigid aluminum to those dimensions with two holes to utilize the two screws that presently hold the trim plate down. By cutting out rectangles for the switches, you can put up to five switches "under the cover" of the ash tray lid. Note that you will want to use either micro switches or low height switches so that the ash tray lid will close without activating any of the switches.

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