Austin Healer
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I thought this might be useful... Many states have laws that mandate that fog lights cannot be used with high beams... It is also advisable to run fog lights through a relay due to the current required.
I've got a pair of Lucas LR8 lamps, commonly called "Square 8's). These were also used on the '68 Shelby Mustangs. I used a Lucas overdrive switch in the hole under the clock. This requires a small body type unit as used in the big Healey for panel lights or overdrive (Moss part # 141-210) and a Lucas 6RA relay (Healey overdrive, Moss part # 542-170). For a "tell tale" on the dash I used an orange idiot light (from some other Rootes product so the lenses would match) in what would be the overdrive warning light location on the dash face.
I mounted the relay on the main bulkhead to the left of the steering column for easy access to the wiring harness grommet.
Here's the schematic for making the connections.
W1 to dash switch. the other terminal on the dash switch goes to ground.
W2 connect to low beam circuit (blue/red tracer) On MK1/MK1a there is a suitable snap connector by the turn signal wires, on MK2's you have to run a wire to the LH headlight sub-harness connector.
C1 Fuse box (brown wires) On the MK2 there is a convenient snap connector for the courtesy lamp feeds (purple wires)
C2 Fog lights and tell tale
Wiring it this way takes all the current load off a very weak Lucas switch and makes it merely a ground interrupt. All of the current draw is on the relay. Including the low beam headlight feed makes the circuit only have power to the fog lights when the low beams are on. The fog lights will automatically turn off when high beams are selected or the headlights are turned off.
I've got a pair of Lucas LR8 lamps, commonly called "Square 8's). These were also used on the '68 Shelby Mustangs. I used a Lucas overdrive switch in the hole under the clock. This requires a small body type unit as used in the big Healey for panel lights or overdrive (Moss part # 141-210) and a Lucas 6RA relay (Healey overdrive, Moss part # 542-170). For a "tell tale" on the dash I used an orange idiot light (from some other Rootes product so the lenses would match) in what would be the overdrive warning light location on the dash face.
I mounted the relay on the main bulkhead to the left of the steering column for easy access to the wiring harness grommet.
Here's the schematic for making the connections.
W1 to dash switch. the other terminal on the dash switch goes to ground.
W2 connect to low beam circuit (blue/red tracer) On MK1/MK1a there is a suitable snap connector by the turn signal wires, on MK2's you have to run a wire to the LH headlight sub-harness connector.
C1 Fuse box (brown wires) On the MK2 there is a convenient snap connector for the courtesy lamp feeds (purple wires)
C2 Fog lights and tell tale
Wiring it this way takes all the current load off a very weak Lucas switch and makes it merely a ground interrupt. All of the current draw is on the relay. Including the low beam headlight feed makes the circuit only have power to the fog lights when the low beams are on. The fog lights will automatically turn off when high beams are selected or the headlights are turned off.
