Torque

Forums

Forums

Guest  

Show or hide header
Welcome Guest, posting in this forum require registration.




Torque » Torque OBD ECU Scanner » Torque Discussion / Ideas » Reading sensor voltage

Pages: [1]
Author Topic: Reading sensor voltage
captainmack
Member
Posts: 3
Post Reading sensor voltage
on: January 17, 2021 (GMT)

Hello, I was wondering if anyone knows if there’s a way to directly read the output voltage of specific sensors using TorquePro. Particularly the MAF sensor. I’m troubleshooting an issue and my workshop manual tells me what voltage the sensor is supposed to output, but not the actual grams/second value (which is all I can find in the app). I’m just hoping there’s a way to read voltage without having to jerry rig and tap into the sensor with a voltmeter. Thanks for any info!

Capp777
Member
Posts: 2917
Post Re: Reading sensor voltage
on: January 17, 2021 (GMT)

It might be useful if you provided vehicle
information.

Your ECU is converting the voltage to g/s so
for giggles you could revert it back to see if
it matches your manual…

[10]*(1/131)

Val{Mass Air Flow Rate}*(1/131)

Pid: 0110

Assumes:

0 g/s = 0 volts

655 g/s = 5 volts

captainmack
Member
Posts: 3
Post Re: Reading sensor voltage
on: January 17, 2021 (GMT)

Yeah I figure it’s a simple linear equation, y = mx + b, just not sure what the m is. I have a 2011 Mazda 6 that’s been throwing a P0101 code, which is the MAF sensor out of range. I’ve replaced the filter and sensor and can’t find any intake leaks but it keeps getting thrown. Right now I’m trying to confirm if the replacement sensor is good. The workshop manual says the sensor should output .68V with the engine off and 1.2V at idle, but doesn’t convert those to the g/s values which is all I can read with TorquePro. I might just have to disconnect the sensor, jumper 12 volts to it, and read the output with a voltmeter.

captainmack
Member
Posts: 3
Post Re: Reading sensor voltage
on: January 17, 2021 (GMT)

Thanks for the advice! Yeah I’ll see what I can do.
Yeah it’s definitely 12V for this one, the manual has wiring diagrams and I’ve measured the input voltage at the connector before to make sure it was getting power and it was showing 12.

Capp777
Member
Posts: 2917
Post Re: Reading sensor voltage
on: January 17, 2021 (GMT)

You might try Forscan app.

My manual reading suggests a typical MAF sensor
uses…

12V feed wire,

5V reference wire from the PCM,

Signal wire back to the PCM,

Ground wire.

Vehicle wiring diagram should be used.

Typical signal voltage of 1.5V to 2.5V at
idle which increases smoothly in a linear
fashion to wide open throttle.

—–

y = mx + b

m is the slope/span.
b is the intercept/zero.

Pages: [1]
WP-Forum by: Fredrik Fahlstad, Version: 2.4
Page loaded in: 0.125 seconds.

  Follow me on twitter