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This time the subject is the ignition switch.
As I look at the wiring diagram in the borrowed Green book (thanks again Duane, I've got my nose buried in it constantly), I see the ignition switch connection chart.
I'm basically using Volvo's convention of switch position, ie, Position 0 is key in, ignition is "OFF"; Position I is accessories only "ON"; Position II is ignition fully "ON"; Position III is "START". However, I'm adding a switch position: -I. This represents the switch with the key out.
It appears to me that there are 10 terminals on the switch labeled as such:
S
50
X (qty 2; right next to each other)
P
30
15 (qty 2; right next to each other)
30 (I assume this is internally shorted to terminal 30 above)
R
Terminal(s) 30 appear to be the pole(s) of the switch; all other terminals are the throws.
So here's what I make of it:
Position -I:
30 is connected to P
Position 0:
30 is connected to S, P
Position I:
30 is connected to X, X, R, S, P
Position II:
30 is connected to X, X, R, 15, S
Position III:
30 is connected to 15, 50, S
So the question is: What does this switch really look like internally? Per the switch schematic in the Green book (p 1) and in Bentley (pp 390-8 & 390-9), it looks like a DP4T in parallel with a SPST... then in Bentley (p 390-10), it looks like a 4P4T... Terminals R & P don't show up anywhere that I can see.
Here's another bit of weirdness: In the Green book, in the many subsections that so nicely describe the circuit, the switch is shown mechanically (a 3/4 view). The weird thing is, in almost every case, only 9 terminals are shown. Only on pp 27, 69, and 71 are all 10 terminals shown. This isn't a big deal, I admit, but inquiring minds want to know.
I realize that in order to get the final answer to all this, I'll probably need to hold a switch in my hand, and use a DMM to sort everything out. Unless someone knows the answer.
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