Problems replacing ignition switch on 75 D100
The old ignition switch for the truck won't run accessories when the key is in the run position (when it's cold out) so I set out to replace the ignition switch as well as the broken turn signal cam.
When I pulled the old switch out and compared it to the new switch, they're pretty similar except the colors are different and the terminals go into different spots on the back of the switch so it's not like I could just look at it and figure it out. According to the schematic, the plug under the dash is as described from left to right:
Starter Relay - Orange (.15v)
Accessories - Light Blue (0v)
Ignition Run - Red (0v)
Ignition Starter - Pink (0v)
Battery - Black (12v)
Ground - Blue/White stripe (0v)
Now in reality when I'm looking at the plug there are 5 pins on the right side of it. Two blank spots and then a pin on the left which I'm guessing connects to the orange wire on the column to light up the shifter display. The original switch has the Blue/White striped wire connected to it but there's no pin in the connector so it was essentially connected to nothing. I can't find evidence of there ever being a wire there when looking at the factory harness under the dash. I also tested for voltage which you can see above.
So I grabbed a multi meter and checked continuity with the switch in all 3 positions.
Old switch:
Acc: Black - Light Blue
Start: Black - Orange - Pink
Run: Black - Red - Light Blue
Everything seems to be working fine. I did this when it was warmer and the light blue wire (accessories) had continuity in the Run position. When the switch is cold there is no continuity there for whatever reason.
So I took the new switch and tested it's continuity so I could figure out the color pattern.
New Switch
Acc: Nothing (possible problem right out of the box)
Start: Red - Brown - Yellow
Run: Red - Black - Blue
Since Red appears in both Start and Run, I'm guessing the new switch is going to use Red as the 12v source while the old switch used to use Black as the source.
Reconnected the wires to the connector and when I was done I ended up with what you see in this picture.
I plugged it back in and when I turned the switch, not a single thing happened. I figured maybe I had the wires wrong. So just to test, I took the old switch, plugged it back in and when I turned the switch, nothing happened either. I'm not sure if I'm now chasing two separate problems at this point because there's no reason why the old switch wouldn't bump the starter over. I know this is a ton of information but I tried to give all I could. Does anyone know where I can start on this?
The old ignition switch for the truck won't run accessories when the key is in the run position (when it's cold out) so I set out to replace the ignition switch as well as the broken turn signal cam.
When I pulled the old switch out and compared it to the new switch, they're pretty similar except the colors are different and the terminals go into different spots on the back of the switch so it's not like I could just look at it and figure it out. According to the schematic, the plug under the dash is as described from left to right:
Starter Relay - Orange (.15v)
Accessories - Light Blue (0v)
Ignition Run - Red (0v)
Ignition Starter - Pink (0v)
Battery - Black (12v)
Ground - Blue/White stripe (0v)
Now in reality when I'm looking at the plug there are 5 pins on the right side of it. Two blank spots and then a pin on the left which I'm guessing connects to the orange wire on the column to light up the shifter display. The original switch has the Blue/White striped wire connected to it but there's no pin in the connector so it was essentially connected to nothing. I can't find evidence of there ever being a wire there when looking at the factory harness under the dash. I also tested for voltage which you can see above.
So I grabbed a multi meter and checked continuity with the switch in all 3 positions.
Old switch:
Acc: Black - Light Blue
Start: Black - Orange - Pink
Run: Black - Red - Light Blue
Everything seems to be working fine. I did this when it was warmer and the light blue wire (accessories) had continuity in the Run position. When the switch is cold there is no continuity there for whatever reason.
So I took the new switch and tested it's continuity so I could figure out the color pattern.
New Switch
Acc: Nothing (possible problem right out of the box)
Start: Red - Brown - Yellow
Run: Red - Black - Blue
Since Red appears in both Start and Run, I'm guessing the new switch is going to use Red as the 12v source while the old switch used to use Black as the source.
Reconnected the wires to the connector and when I was done I ended up with what you see in this picture.
I plugged it back in and when I turned the switch, not a single thing happened. I figured maybe I had the wires wrong. So just to test, I took the old switch, plugged it back in and when I turned the switch, nothing happened either. I'm not sure if I'm now chasing two separate problems at this point because there's no reason why the old switch wouldn't bump the starter over. I know this is a ton of information but I tried to give all I could. Does anyone know where I can start on this?