5 Terminal B&S ignition switch

Geochurchi

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Hi All , B&S Vangard 16 HP , switch has R B S A I. What I used R from rectifier, B battery , S start, and A for accessories, not sure what the I terminal would be for, motor has a magneto ignition, does this switch short out internally to kill the motor? I haven’t started it yet , only turned it over,
Geo ??
 

Scrubcadet10

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I'm going off of my Memory here, i should be the kill wire from the ignition coil(s)
Someone may KNOW this off the top of their head.
 

StarTech

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Need equipment numbers to look the switch and probably a wiring schematic.
 

Rivets

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I is normally IGNITION, which would be your kill wire connection.
 

StarTech

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I is normally IGNITION, which would be your kill wire connection.
Got to sure of the switch and wiring as one switch I looked up having "I" applied 12v which would destroy the magneto ignition coil electronics.

As I said equipment numbers are needs along the pn of the switch.
 

Rivets

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Please post which switch you or talking about?? That would be a new one for me.
 

ILENGINE

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Got to sure of the switch and wiring as one switch I looked up having "I" applied 12v which would destroy the magneto ignition coil electronics.

As I said equipment numbers are needs along the pn of the switch.
Very true. I would normally mean 12 volt coil power as opposed to the normal M on the switch for kill wire grounding systems.
 

StarTech

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Rivets commented>
Please post which switch you or talking about?? That would be a new one for me.
Oregon 33-389 (Kohler 48 099 01, Onan 378-0385)

For battery coil ignition. 5 spade terminal. 3 position
 

Rivets

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Generically:
"B" is for the input from the battery source'
"R" is typically to indicate "red wire" out to components that need 12V power in the RUN position of switch (Cub to name one).
"S" indicates starter control out.
"L" can indicate lights if lights function is part of the key switch duties (may have other functions on different machines.
"A" might be used to power accessory components in some applications and may or not be a separate position from RUN on the switch. On some applications "A" is simply an additional output to lessen the total load on other outputs of the switch.
Typically on some applications you might also find these letters:
"G" (ground), provides for a separate ground wire to the switch body in applications where the switch is mounted in a nonmetallic panel.
"M" (magneto), is found in applications where the key switch functions to kill the ignition spark by shunting the magneto primary wire (kill wire) to ground when the key is turn OFF.
”I” (Ignition) is found in applications which use a battery ignition system, not a magneto ignition system.

Star you are correct, if you have a battery ignition system, using a switch with an “I” terminal will blow the module. Vanguard, Briggs, uses a magneto ignition.
 

Geochurchi

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All set, thanks for the advice, I got a switch with the M terminal.
Geo??
 
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