Help with schematic switch symbols

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slipnfall
Posts: 1819
Joined: Mon Jan 13, 2003 9:43 am
Car: '06 D40

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Hi there, I have a FSM for my 92 cpe. I am looking for some help deciphering the schematic symbols for switches. I have attached an example, the popup retract switch. It appears to be a truth table, but I would like some help figuring it out(what's connected to what for each condition). I have an electronics background but this one has me stumped. Any insight is appreciated!

Thanks!-Jamie



slipnfall
Posts: 1819
Joined: Mon Jan 13, 2003 9:43 am
Car: '06 D40

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..oO0( bump )0Oo..

Anyone? Do all the right-side connections get connector together for the 'ON' position, and all the left side connections together for 'OFF'? Is it truely a logic truth table?

FactoryStock
Posts: 22
Joined: Fri Feb 27, 2004 4:22 pm
Car: 1991 Nissan 240SX SE

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OK, you got my curiousity up, so I checked my FSM to get an explanation. In the "General Information" section on page GI-7 (1991 FSM) "How To Read Wiring Diagrams", it explains how the "truth table" you refer is interpreted. Read across the top for the switch states, e.g. "OFF" and "ON", then read down the left side to see which terminals are connected together for that state. Not sure if this helps. BTW what are you trying to figure out from the wiring diagram?

FactoryStock
Posts: 22
Joined: Fri Feb 27, 2004 4:22 pm
Car: 1991 Nissan 240SX SE

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Further clarification: The "sub-states" under "OFF", "1ST", and "2ND" look to be: A=Open, B=Closed, C="Opened and closed after headlamps go off".

Also, switch tables with terminals on the left side are shown on the more detailed wiring diagrams for headlamps in the FSM. For example:

State: "OFF" and "C": 5-6, 8-9, 27-28 are connected together.

slipnfall
Posts: 1819
Joined: Mon Jan 13, 2003 9:43 am
Car: '06 D40

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Factory - thanks! I completely missed that section of the FSM. I must have read that darn thing front to back already...

Anyways, I'll take a look, then post a more verbose reponse.

Thankfully,-Jamie

slipnfall
Posts: 1819
Joined: Mon Jan 13, 2003 9:43 am
Car: '06 D40

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FactoryStock wrote:State: "OFF" and "C": 5-6, 8-9, 27-28 are connected together.


Factory, Thanks for pointing me in the right direction. What was fowling me up was my poorly printed FSM. I did not see the connection between the circles on top one another(in the switch state table). This makes perfect sense now. What I thought was a '1', or a logic high was actually an interconnect. Anyways, that helps immensly! Reason I'm digging into this is because my retract switch has been re-wired. Prior owner used the switch for aftermarket fog lights(grr, they ran wires/relay all the way from the dash to the front of the car, but were too *$*# lazy to put in another switch). My guess is they didn't see the point of the retract switch, since the headlight switch retracts them for you. So yeah, now the hunt begins for all the proper wires...

Once again, thx for the response.-Jamie

FactoryStock
Posts: 22
Joined: Fri Feb 27, 2004 4:22 pm
Car: 1991 Nissan 240SX SE

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Glad I could be of some help and I learned something in the process. Good luck with the rewiring!


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