Measurements for testing a Cummins/Titan (red/white/black) switch (NOT a CSP5 OBD II switch) with a meter:
The wire should be soldered into the board in the following order
Black above the "C"
White above the "um"
Red above the "mm"
Test Voltage with switch plugged in and key on, test resistances with switch unplugged.
Red to white resistance = 2200
Black to red voltage = 5V
Black to white:
Pos 1: resistance = open Voltage = 5.0V
Pos 2: resistance = 5600 Voltage = 3.5V
Pos 3: resistance = 2200 Voltage = 2.5V
Pos 4: resistance = 1000 Voltage = 1.5V
Pos 5: resistance = 270 Voltage = 0.5V
PRO TIP: If when you try to insert the pins they don’t stay in the gray connector… If the red insert inside the gray connector is pushed too far down OR if you plug the connector in and somehow push the red connector down BEFORE you insert the pins, then you need to pull the red insert back out FIRST. To do this, you can either stick a hook or probe into one of the two bigger slots on the red insert and pull it up slightly OR grab the small protruding piece of the red insert with a small pliers and pry it up that way We hope this helps you and your customers!
Here is a picture of a Cummins/Titan switch for your reference!