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4 Wire TPS
Posted: Fri Jun 25, 2010 1:36 pm
by Blatzy
I am in the orocess of installing MSII V3 on a 1987 Suzuki Samari unsing EDIS 4 and the throttle body off a 1991 geo Tracker. I have sucessfully installed Ms on GM v6 but the import is new. what I am trying to figure out is the TPS wiring. The TPS on this system uses 4 wires does anyone know how the wiring works? what do I do with the extra wire? Or even which wire are which?
Thanks
Blatzy
Re: 4 Wire TPS
Posted: Mon Jun 28, 2010 10:05 am
by Matt Cramer
One of the wires is going to be an on-off switch; the remaining three work like a normal potentiometer TPS.
Re: 4 Wire TPS
Posted: Mon Jun 28, 2010 5:09 pm
by Blatzy
Thanks Matt
Re: 4 Wire TPS
Posted: Mon Jun 28, 2010 5:34 pm
by DonTZ125
Matt Cramer wrote:One of the wires is going to be an on-off switch; the remaining three work like a normal potentiometer TPS.
An ON-OFF Switch?! On a TPS?! Or do you mean a limit / end of travel switch?
Re: 4 Wire TPS
Posted: Tue Jun 29, 2010 5:15 am
by Matt Cramer
I meant on/off as its type of output; usually they indicate that the throttle is closed. Why they felt a need to add a switch for that when the ECU could tell from the voltage reading that the throttle is closed, I'm not sure.
Re: 4 Wire TPS
Posted: Tue Jun 29, 2010 8:04 am
by sundie
Matt Cramer wrote:I meant on/off as its type of output; usually they indicate that the throttle is closed. Why they felt a need to add a switch for that when the ECU could tell from the voltage reading that the throttle is closed, I'm not sure.
I think they're usually a WOT switch, and they go to the ECU for the transmission control as a simple "don't switch gears" thing.
Re: 4 Wire TPS
Posted: Tue Jun 29, 2010 9:59 am
by Matt Cramer
Seems different manufactures did both ways.
Re: 4 Wire TPS
Posted: Tue Jun 29, 2010 5:53 pm
by sundie
well, it's easy enough to find out.
Put your meter ground to the apparent ground (usually black, unless it's a german car, then it's usually brown), put your meter red lead on each of the other 3 wires, and see what happens. One of them will (probably) go 0 ohms (continuity) at either full open or full closed.
VW Passat auto 16v's had a separate mechanism/connector for WOT that went to the transmission valve control - which is real handy for a safety for NOS, or anything else you'd like to ensure only happens at WOT. I can't think of what you'd need a "fully closed" switch for really.
Re: 4 Wire TPS
Posted: Wed Jun 30, 2010 4:39 am
by Matt Cramer
Some ECUs seem to have used that for idle control.