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IppoJ
01-26-2023, 03:48 PM
Anyone here fully understand Lucas' switch diagrams?
I'm a legit electronics tech but I've only seen the schematic type switch diagrams before.

The way I'm reading this diagram, terminals 1 and 2 are electrically the same in positions 2, 3 and 4. SO, I should be able to use terminal 1 instead of 2 for the S3 ignition switch? 14211

siiirhd88
01-26-2023, 10:42 PM
Terminal 1 is where the solid brown incoming power is connected. The power is isolated when the switch is 'off', except there is usually another brown wire on Terminal 1 that is power to the horn push. With the key turned to 'on' power goes out the white wire on terminal 2, to the ignition system and fuse box. With the key turned to 'start' power goes out the white with red trace wire to the starter solenoid coil on Terminal 3. Not all switches have an aux position.

Bob

roverp480
01-27-2023, 05:30 PM
Terminal 1 is where the solid brown incoming power is connected. The power is isolated when the switch is 'off', except there is usually another brown wire on Terminal 1 that is power to the horn push. With the key turned to 'on' power goes out the white wire on terminal 2, to the ignition system and fuse box. With the key turned to 'start' power goes out the white with red trace wire to the starter solenoid coil on Terminal 3. Not all switches have an aux position.

Bob
Further to the above, the diagram in question appears to be for Diesel vehicles , terminal 5 HTR is for the heater plugs which need energising before the start position . The terminal 4 AUX is designed to disconnect while cranking . Things like heater or similar might be connected to this

IppoJ
01-27-2023, 06:55 PM
Thanks for the confirmation. It's in and working.

But next question is about the above mentioned glow plug circuit. I'll start a new thread though.