Does anyone have the map sensor scaler multiplier and offset for a Bosch 4 bar T map sensor?
Or could someone explain how to calculate it please?
https://www.bosch-motorsport-shop.co...20200710031029
Attachment 24548
Attachment 24549
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Does anyone have the map sensor scaler multiplier and offset for a Bosch 4 bar T map sensor?
Or could someone explain how to calculate it please?
https://www.bosch-motorsport-shop.co...20200710031029
Attachment 24548
Attachment 24549
Scalar should be 437.5. Offset should be 6.25.
How do you calculate it?
It's a variation on a slope intercept; y=mx+b.
m=(p2-p1/(v2-v2). In this case; m=(400kpa-50kpa)/(4.5v-0.5v) <- this is right off the Bosch chart.
So, m=87.5.
Multiply that by the sensor input voltage of 5v. Scalar=87.5*5v = 437.5
To find the offset, you can either calculate the offset the standard slope/intercept way, or do the voltage check way.
Standard way is to plug in the values in to y=mx+b.
Re-write to b=y-(mx). b=400-(87.5*4.5) = 6.25
Voltage Check way is to back calculate using the sensor.
Your Scalar is telling the ECM that 4.5v is 393.75kPa (437.5*(4.5v/5v)). That's obviously too low, so we take the listed valve from the Bosch sheet, and find the difference. 400kPa-393.75kPa = 6.25kPa
The formula is Offset = P2-(Scalar*(V2/5v)).
Which in this case is Offset=400-(437.5*(4.5v/5v)) = 6.25
Hope that helps and makes sense.
Yes, makes sense. Took me a couple of times reading it and writing it down to understand it. Thank you so much for your help. Very much appreciated and great explanation.