Early Falcon Car Club

of Western Australia

Reverse Order

It's always nice to be able to let the car behind you know when you are going to reverse without having to make some rude gesture out of the rear windscreen especially on those occasions when you are going to back into a parking bay and the person behind you is tailgating. Although most of the Early Falcons did not have reversing lights many do have the parts already in the car that just need to be hocked up and what's more the indicators will still work while the reversing lights are on.

		The indicator loom has an unused wire that when powered up will bring on the two rear amber indicator lamps together. Also the automatics, Ford's 2 speed and the Borg-Warner 3 speed have ignition cut-off switches that incorporate a reversing light switch. While the manual 3 speed did not have any switch fitted as standard there was an after market option available. Although all this hardware was fitted to the vehicles with auto gearboxes almost none were in service when they left the factory.
Fig 1. The wiring loom of the indicator showing the Green wire with Green plug also note how dull the connector is, well worth a clean up with a soft wire brush to improve electrical conductivity.

The Ford o Matic 2 speed ignition cut-off switch is mounted under the steering column inside the car and has 4 terminals, the two on the right are for the ignition cut-off circuit and allow the car to be started only if it is in Neutral or Park while the two terminals on the left are the reversing light circuit and will be closed when reverse is selected. The switch works by each pair of contacts wiping over some strips of brass mounted in a plastic insulator fitted to the gearshift column
		Fig 2. The Ford-O-Matic 2 speed auto ignition cut-off inner brass strips and insulator left and the outer terminals right. Quite often the reversing terminals were not fitted, Ford left blank holes.

		The Borg-Warner uses a break-before-make switch that is mounted on the passenger side of the gearbox. This switch also has four terminals and a plunger that is spring loaded in the reversing lights 'on' position, exiting the switch as the two splayed terminals. When the plunger is pushed all the way in, the 'start' positing, the two parallel terminals are closed and when the plunger is only part way in neither of the two pairs of terminals are closed, this is the no reverse and no start position as used for the Drive, L to H range.
Fig 3. The Borg-Warner ignition cut-off switch, the Splayed terminals left and right are for the reversing light and the Parallel terminals top and bottom are for the ignition cut-off.
		Hint if the terminals are badly bent it can be difficult to tell which are the splayed and the which are the parallel terminals but it will be seen from the photo Fig 3. that there is a small shoulder between the parallel terminals and the centre boss.

The after market reverse switch kits consisted of a spring clip, micro-switch plus bracket and a hose clamp. The clip was fixed to the selector arm at the foot of the outside of the steering column and the micro-switch and bracket held in place with the hose clamp. Quite a simple issue to build today as the micro-switches are still very much available from stores like Radio Shack and Dick Smiths.

Fig 4. The lower section of the steering column showing the control arm and the spring clip shown in green the micro-switch button shown in red and the hose clamp holding the total assembly to the column.
Although this diagram symbolises an auto, single control arm, this type of switch was more often used with the dual control arms of the manual greaboxes.

		The wiring is very simple, run a wire from the accessory point at the centre rear of the ignition switch via an inline fuse, 2 amps should be fine, then to the reversing switch and from there to the green wire with the green plug on the indicator loom. Hint the metal part of this connector will most likely need a bit of a clean as it will have been exposed to the elements for the past few years.
Fig 5. Wiring Diagram

Fig 6.
The selector cam inside the Borg-Warner S3

Here there is a steel strip clipped to the side of the selctor cam that regulates the depth of the switch plunger.
The straight length of the steel strip between L and H is the section where the plunger strikes when in Drive. Then moving right the hump where the plunger strikes when in Neutral as it is in the photo and then further right to the valley where the plunger strikes in reverse and finally the hump where the plunger strikes for Park.

Fig 7. How it works

The diagram to the left shows the inside of the switch and the steel strip on the gearbox cam.

It can be seen that when the selector is in the Drive position the moving contact at the end of the plunger is midway between the two pairs of fixed contacts and neither circuit is closed. No power can get to the reversing lights or the starter solenoid.

While in the Neutral position the plunger is being pushed in by the steel strip and the moving contact connects with the parallel fixed contacts and the starter solenoid circuit is closed and the starter motor can now be turned over.

It the next position the plunger has been allowed to travel to its fullest, spring loaded, position and the moving contact is now connecting with the splayed contacts and the reversing circuit is closed and the starter circuit open. The reversing lights come on but the starter motor cannot be turned over.

Finally the Park position duplicates the Neutral position in that the plunger and the moving contact is positioned so the solenoid circuit is conduting and the reversing lights are open circuit.

Adjustment of the switches can be a pain. - The Ford o Matic has the plastic sleeve that holds the brass strips that can be moved on the gear selector shaft but it is had to get at, however there is some side-to-side adjustment in the switch housing mounted under the steering column.

The Borg-Warner switch is adjusted by screwing the switch in or out of the gearbox housing. The best way is to have the car in the Drive or L to H positions, without the engine running :) and then with a test lamp across the reversing terminals screw the switch into the housing until the light goes out then stop screwing and lock the switch with the locknut. Now place the car selector in to Park or Neutral and turn the key to see if the starter solenoid will work, if not screw the switch in some more.

DISCLAIMER While this method has been tried and works, NO responsibility will be excepted by the Author, the Club or any of its Members.