Input Signal Wiring
25
© 2009 Link
TPS Wiring
7.4
Engine Coolant Temperature Sensor
Engine coolant temperature is required primarily for fuel enrichment during cold starting and
during the warm-up period that follows. This sensor should always be mounted on the
engine side of the thermostat.
G4 ECU's can measure the temperature using a thermistor (NTC or PTC) sensor or a
sensor with a 0-5V output. Any sensor calibration is permitted.
Thermistor sensors have a resistance that changes with temperature and are commonly
used in automotive applications. When wiring thermistor sensors the polarity is NOT
important. An Analogue Temp wire should be connected to one terminal on the sensor
while the other terminal must be connected to the Sensor Ground (green) wire.
When using a sensor that produces a 0-5V output or in piggy back application where a
factory ECU is already providing the temperature sensor pull-up resister, connect the ECT
signal to an Analogue Volt channel.
G4 ECU's are compatible with any NTC or PTC thermistor sensor. The recommended
sensor is a Bosch 0 280 130 026 sensor. A number of pre-calibrated sensor options are
also provided in PCLink Tuning Software. Note that most factory sensors will use the
Standard Bosch NTC calibration. In order to use a sensor with a different calibration you will
need to know how the sensor’s resistance changes with temperature and enter this
information into the ECU via PCLink Tuning Software.
7.5
Intake Air Temperature Sensor
Using an inlet air temperature sensor allows fuel and ignition corrections to be made for
changes in the temperature of the air entering the engine. The air temperature sensor must
be set-up to most accurately measure the temperature of the air entering the engines
combustion chambers. On a naturally aspirated engine this normally means any position
between the air filter and inlet manifold. However, on a turbocharged/supercharged engine
the sensor must be placed AFTER turbocharger and any inter-cooler.
On most applications (both naturally aspirated and turbocharged) the recommended
mounting position is in the inlet pipe just before the throttle plate. The sensor may also be
placed in a section of the inlet manifold that is subject to high airflow. However, in some
applications the inlet manifold may get very hot and heat soak the sensor causing a reading
that is not representative of the air entering the combustion chambers.
It is very important on a turbocharged/supercharged engine that the air temperature sensor
can react fast enough to track the rapidly changing temperature. For this reason, an open
element sensor is required. The recommended sensor is a Bosch 0 280 130 085. On
naturally aspirated engines this sensor may be substituted for a 0 280 130 039, which is
cheaper and easier to fit.
G4 ECU's are designed to measure the temperature using a thermistor sensor. These
sensors have a resistance that changes with temperature and are commonly used in
automotive applications. When wiring thermistor sensors the polarity is NOT important. The
Inlet Temperature Sensor must be connected to the Sensor Ground (green) wire and
an Analogue Temp wire.
G4 ECU's are compatible with any NTC or PTC thermistor sensors. The default calibration
is for either of the Bosch sensors listed above. In order to use a sensor with a different
calibration you will need to know how the sensor’s resistance changes with temperature and