This cable allows the user to install a GM or AEM IAT sensor and any GM 3-bar style MAP sensor without the hassle of cutting wires on the factory wiring harness. Just plug this harness in to your stock MAS connector and your IAT/MAP sensors and you’re ready to go!
When changing your settings in the application for ECMLink to recognize the new sensors, the IAT sensor is wired to the factory Intake Temp input pin, and the MAP sensor is wired to the factory Baro input pin.
2G NOTE: The baro input of the 2G ECU may not be compatible with aftermarket sensors. The 2G ECU has a 3.3K ohm pull-down resistor (R39), which may (probably will) put more load on the sensor than it can drive properly. For example, a GM 3-bar sensor can only drive this input to 1.76 volts at maximum pressure. The GM 3.3-bar sensor seems to have a bit lower output impedance and will drive the 2G baro input a little higher, but it’s still unsuitable. Short of removing R39 from the ECU (described here), the 2G baro input is suitable for use only with very low impedance sensors (even a 50-ohm output impedance will produce a little over 1% of voltage offset). Since most sensor designs have a resistor in series with its output for protection, the 2G ECU’s baro sensor input is probably not suitable for use with most sensors. HOWEVER, the MAP sensors we offer work without any modifications.
The 1G baro input doesn’t seem to suffer from this problem. It has an input impedance similar to the 2G MDP sensor input’s 100K ohms).
ADDITIONAL NOTE #1: If you order IAT and/or MAP sensors along with this cable, you will NOT receive the wiring pigtails that normally come with those sensors unless you specifically ask for them (in the comments box during checkout).
ADDITIONAL NOTE #2: If for some reason you decide to cut off the GM-style MAP connector to wire in a different one, you will need to know the assignment of each wire. See below:
Pink: +12V power