Problem: The intake temperature reading on my Emerald K6 ECU is locked at 40˚c.
Sensor: Ford combined MAP/temperature sensor, CF 331 (4S4G-9F479-AC)
Hypothesis: The voltage mapping is wrong for this sensor putting it outside of the readable ranges.
- The Emerald K6 documentation sucks monkey and doesn't specifically address information about the electrical connection of the intake air temperature sensor.
- Emerald simply say "Input > Air Temperature > Yes, standard Bosch or user programmable characteristic"
- They don't offer electrical connection information. Since the Bosch NTC sensor is a resistance type sensor I have to assume that there's an internal pull-up and I'll assume that it's a 1k Ohm resistor. ('Cause that's how things tend to be)
- The table below is best guess/estimated values based on 5vcc in and a 1k Ohm pull-up resistor.
Since the Bosch/FoMoCo TMAP and Bosch NTC have practically the same mapping, it's safe to assume that as long I can read a resistance across the pins it should be good to use this sensor. It may be the case that there's a wiring issue in the loom that I'll need to track down but a good test will be to try with a different sensor first, since I have a delphi sensor just chillin' out, I can plug that in to verify that the wiring is good.