New Ignition key switch!!!

I am replacing the old switch with a new switch and i have a few questions.

1. I had ten wires coming from thew old switch and i have only six from the new one. Which wires should i group together to make this switch work properly. It is on a 99 mercury 90hp

OLD SWITCH

2 black
2 purple
1 red
1 red w/purple stripe
1 yellow w/black stripe
2 black w/yellow stripe
1 yellow w/ red stripe

NEW SWITCH

blue
red
black
yellow w/red stripe
purple
black w/yellow stripe


the question is...which wires go to which?? Thanks for the help guys!!

Re: New Ignition key switch!!!

You might have to do what most of the rest of us do when confronted with a similar situation.

Gather any available wiring schematics, and a volt ohm meter with continuity tester, along with a note pad or two and writing material

Take the new switch and decipher what each wire does in relation to any other for each process and note those down.

Through the use of the voltmeter, tester, wire tracing to motor, and any wiring diagrams, decipher each harness wire's duty or need and note those down.

Then compare notes to determine that the new switch can provide the desired functions, and the applicable connections you need to make.

Sometimes it's simple and sometimes not, but that's how I've done them before.

Sometimes the new switch will have extra connections not used for a particular application, and sometimes a switch won't have enough connections to do what needs to get done and has to be exchanged for one that will.

Re: New Ignition key switch!!!

The back of the switch should have letters next to each termal.

A = accessories. +12 volts on this terminal when the key is on.
B = Battery. This is the +12 volt feed from the engine harness.
C = Choke. Provides +12 volts to the choke/primer solenoid when the key is pushed in while starting.
I or M = Ignition/Magneto
M = Magneto
S = Start solenoid. +12 volts on this terminal when the key is in the start postion.

This diagram is as close as I can get.