Ignition Switch Wiring

by Pat Walsh and Jim Thompson

Pat Walsh writes:

Below is the ignition switch wiring chart from MY '71 Westy. The switch is a replacement from RMMW, but the wires all matched colors with the exceptions noted below. I can't swear that the PO didn't change any wiring, but it all LOOKS original, with the possible exception of maybe the black wire going to the light switch. BUT, it DOES all work, including the coil getting 12V in the start position. :-)


   WIRE                  FROM/TO                         DESCRIPTION
--------             ----------------               -------------------

Red/Black            from switch to starter         12V when in "START" position
Black                from switch to fuse box and
                     ignition coil                  12V when in "ON" and
                                                    "START" position
Black/Yellow(1)      from switch to light switch    12V only in "ON" (not
                                                    "ON" & "START")?
Red                  from battery to switch         12V at all times (straight
                                                    from battery)
Brown/Blue(2)        door buzzer                    connected to GND when key
                                                    is in ignition
Blue/gray            not used

1. Connecting wire is Black, not Red/Black as shown in book. 2. This wire is shown as Brown in book. Also, the connecting wire is White/Black, not Brown as shown in book.

Note from Jim Thompson at a later date regarding the wiring of a '69 bus replacement ignition switch:

Jim Thompson writes:

This Grey wire is an "accessory" wire used on models that never made it to the US. In fact, it's not widely known, but the replacement switch has an "accessory" position, which due to the design of the USA/Canadian market steering locks is not accessible for some stupid reason I've never been able to fathom.

The original switches had 3 positions, Off, On and Start. The Replacement Switch has 4 Positions (clockwise starting from the left), Accessory, Off, On and Start.

It's important that before installing this switch to take a screwdriver and check the correct position of the movable slot of the switch. Check to see if has 4 positions. If so, be sure that it's in the second position (Off) before attaching it to the steering lock. If it's a 3 position switch, make sure it's in the first position (Off).

I usually tell people to loop the wire under the dash and tape the end up so it doesn't contact anything to short out. For people with Stereos and Amplifier combinations, it makes a great sensing wire to tell the amplifier to turn on, but I usually wire my music to play on a "hot all da time" circuit.