Open/Closed loop indicator

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peepsalot

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Black 03 MSP

• Apr 20, 2005

• #1

Is there a way to build something like this, or buy one that is cheap? I don't need a display, just something that will switch between high and low voltage to tell one way or the other(doesn't matter if open/closed are high or low).

I know you can get OBD scanners that will tell you this when hooked to a laptop, but I just need something that will send a signal when in closed loop or not. Is going through OBDII the only way? Is there some wire that tells this, or do you have to have complicated circuitry to communicate with the ECU and ask what mode it is in?

 

P

peepsalot

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Black 03 MSP

• Apr 20, 2005

• #2

Or alternatlively, does anyone know the exact parameters that the ECU would use to determine when to switch betwee open and closed loop.

 

B

BradC

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03.5 Ti Gray MSP

• Apr 20, 2005

• #3

Not completely sure, but don't most switch when you hit WOT? If that is how it works, maybe it uses TPS signal?

 

P

peepsalot

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Black 03 MSP

• Apr 22, 2005

• #4

Yeah, it should switch to open loop when you are WOT in general, but it doesn't have to be 100% throttle to do it, and I think in lower rpms at WOT it even stays closed loop. It is a specific set of conditions that has to happen, rpm, tps, coolant temp, etc.

Anyone?

 

L

low_psi

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ms|slowtege #399

• Apr 22, 2005

• #5

Its a mix of conditions and I'm not sure if anyone other than Mazda's engineers know all the parameters that contribute to closed/open loop operation.

 

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igdrasil

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12psi Protege5

• Apr 26, 2005

• #6

Yes, there is one company that has a Open/Closed loop monitor with leds and its very cheap. Im trying to remember the page.... ok here...there you go:

http://www.autospeed.com/shop/category_906/product_1001300008/browse.html