2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 1193
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The motor temperature sensor (MTS) is a non-serviceable part of the drive motor generator assembly. The MTS sensor is a thermistor, or a resistor
that changes value when the temperature changes. The sensor has a negative-temperature coefficient. This means that as the temperature increases,
the resistance decreases, and as the temperature decreases, the resistance increases. The motor control module (MCM) supplies about a 5-volt
reference signal to the sensor and measures the voltage drop in the circuit. When the motor is cold, the sensor resistance is high and the MCM
detects high signal voltage. As the motor temperature increases, the resistance of the sensor decreases, which lowers the signal voltage.
Conditions for Running the DTC
P0A2B and P0A31
* DTCs P0A2C, P0A2D, P0AEF, P0AF0, P0BD3, P0BD4, P0BDD, P0BDE are not set.
* Ignition ON after the engine has been OFF for at least 6 hours.
* Average of phase U, V, W inverter temperatures is greater than -12掳C (+10掳F).
* Motor temperature is greater than -40掳C (-40掳F).
P0A2C, P0A2D, P0A32 and P0A33
The ignition is ON.
Conditions for Setting the DTC
P0A2B and P0A31
* The average of the three motor phase sensor temperatures and the motor temperature are not within 28掳C (50掳F) of each other at ignition ON.
* The DTC sets within 3 seconds when the above condition is met.
P0A2C and P0A32
* Motor temperature sensor signal is less than 0.29V.
* The DTC sets within 3 seconds when the above condition is met.
P0A2D and P0A33
Motor temperature sensor signal is greater than 4.42V.
If this condition is observed at Ignition ON, the drive motor generator must operate at greater than 20 Nm (14.75 lb ft) of torque for a cumulative
time of 1.5 minutes before the DTC will set.
If this condition is observed after Ignition ON, the DTC will set within 3 seconds when the above condition is met.
Action Taken When the DTC Sets
* DTCs P0A2B-P0A2D, P0A31-P0A33 are Type B DTCs.
* The HPCM commands the SERVICE HYBRID SYSTEM message to display on the instrument panel.
Conditions for Clearing the DTC
DTCs P0A2B-P0A2D, P0A31-P0A33 are Type B DTCs.
Diagnostic Aids
* The motor temperature sensor can be damaged by excessive electric current. Test the sensor for an open condition whenever a short to
voltage condition is observed.
