Part 1
2 Monitoring FunctionsIn the following subchapters all OBD I/OBD II relevant fault paths are described.
2.1 Stator temperature sensor monitor
2.1.1 Stator temperature sensor "out of range high" (P0A2C)
Goal of this diagnosis is to check the stator temperature sensor against its upper physical/technical limit.
2.1.1.1 Monitoring strategy
If the sensor value is higher than a threshold value the "stator temperature sensor out of range high" is detected.
2.1.1.2 Enable condition
No enable condition necessary.
2.1.1.3 Chart(s) and flow chart(s)
2.1.2 Stator temperature sensor "out of range low" (P0A2D)
Goal of this diagnosis is to check the stator temperature sensor against its lower physical limit.
2.1.2.1 Monitoring strategy
If the sensor value is lower than a threshold value the "stator temperature sensor out of range high" is detected.
2.1.2.2 Enable condition
No enable condition necessary.
2.1.2.3 Chart(s) and flow chart(s)
2.1.3 Stator temperature sensor "rationality fault" (P0A2B)
Goal of this diagnosis is to check if the sensor signal is plausible.
2.1.3.1 Monitoring strategy
The sensor signal will be checked against the heat sink temperature sensor and the PCB temperature sensor by executing a cross check. The diagnosis will only be done after a sufficient engine off time.
2.1.3.2 Enable condition
- engine off time is greater than 6 hours
- no electrical temperature sensor failure detected
2.1.3.3 Chart(s) and flow chart(s)
2.2 Heat sink temperature sensor monitor
2.2.1 Heat sink temperature sensor "out of range high" (P0AF0)
Goal of this diagnosis is to check the heat sink temperature sensor against its upper physical/technical limit.
2.2.1.1 Monitoring strategy
If the sensor value is higher than a threshold value the "heat sink temperature sensor out of range high" is detected.
2.2.1.2 Enable condition
No enable condition necessary.
2.2.1.3 Chart(s) and flow chart(s)
2.2.2 Heat sink temperature sensor "out of range low" (P0AEF)
Goal of this diagnosis is to check the Heat sink temperature sensor against its lower physical/technical limit.
2.2.2.1 Monitoring strategy
If the sensor value is lower than a threshold value the "heat sink temperature sensor out of range high" is detected.
2.2.2.2 Enable condition
No enable condition necessary.
2.2.2.3 Chart(s) and flow chart(s)
2.2.3 Heat sink temperature "rationality fault" (P0AEE)
Goal of this diagnosis is to check if the heat sink sensor signal is plausible.
2.2.3.1 Monitoring strategy
The heat sink sensor signal will be checked against the stator temperature sensor and the PCB temperature sensor by executing a cross check. The diagnosis will only be done after a sufficient engine off time.
2.2.3.2 Enable condition
Engine off time is greater than 6 hours
No electrical temperature sensor failure detected
2.2.3.3 Chart(s) and flow chart(s)
2.3 PCB temperature sensor monitor
2.3.1 PCB temperature sensor "out of range high" (P0AF5)
Goal of this diagnosis is to check the PCB temperature sensor against its upper physical/technical limit.
2.3.1.1 Monitoring strategy
If the sensor value is higher than a threshold value the PCB temperature sensor "out of range high" is detected.
2.3.1.2 Enable condition
No enable condition necessary.
2.3.1.3 Chart(s) and flow chart(s)
2.3.2 PCB temperature sensor "out of range low" (P0AF4)
Goal of this diagnosis is to check the PCB temperature sensor against its lower al/technical limit.
2.3.2.1 Monitoring strategy
If the sensor value is lower than a threshold value the PCB temperature sensor "out of range high" is detected.
2.3.2.2 Enable condition
No enable condition necessary.
2.3.2.3 Chart(s) and flow chart(s)
2.3.3 PCB temperature sensor "rationality fault" (P0AF3)
Goal of this diagnosis is to check if the PCB temperature sensor signal is plausible.
2.3.3.1 Monitoring strategy
The PCB temperature sensor signal will be checked against the stator temperature sensor and the heat sink sensor by executing a cross check. The diagnosis will only be done after a sufficient engine off time.
2.3.3.2 Enable condition
- engine off time is greater than 6 hours
- no electrical temperature sensor failure detected
2.3.3.3 Chart(s) and flow chart(s)
2.4 Phase U/W current sensors monitor
The DMCM is using two phase current sensors. One sensor is used to measure the current in phase U and the other sensor to measure the current in phase W. The diagnostic functions for both sensors are similar and the monitoring strategies are described in the following subchapters. For both sensors separate DTCs are used.
2.4.1 Phase U/W current "out of range high" (P0BE8)/ (P0BF0)
Goal of this diagnosis is to check the phase U/W current against its upper physical/technical limit.
2.4.1.1 Monitoring strategy
If the sensor signal of phase U/W sensor is higher than a upper threshold the phase U/W current "out of range high" is detected.
2.4.1.2 Enable condition
No enable condition necessary.
2.4.1.3 Chart(s) and flow chart(s)
2.4.2 Phase U/W current "out of range low" (P0BE7/ P0BEF)
Goal of this diagnosis is to check the phase U/W current against its lower physical/technical limit.
2.4.2.1 Monitoring strategy
If the sensor signal of phase U/W sensor is lower than a threshold the phase U/W current "out of range low" is detected.
2.4.2.2 Enable condition
No enable condition necessary.
2.4.2.3 Chart(s) and flow chart(s)
2.4.3 Phase U/W current "rationality fault" (P0BE6/ P0BEE)
Goal of this diagnosis is to check if the phase U/W current is plausible. The diagnosis is separated in two parts which are active either if the system state is either in
- init
or in state
- drive
2.4.3.1 Phase U/W current sensor rationality fault during initialization
2.4.3.1.1 Monitoring strategy
During the system state init the current has to be zero because the contactors of high voltage battery are open. If in this system state the current sensors offset exceeds an upper threshold or lower threshold a phase U/W current "rationality fault" is detected.
2.4.3.1.2 Enable condition
- system state is "init"
2.4.3.1.3 Chart(s) and flow chart(s)
2.4.3.1.4 Monitoring strategy
During the system state drive the symmetry around zero amps of sinusoidal current is checked. If the arithmetic mean of the signal (average current) exceeds a higher or lower limit a phase U/W current "rationality fault" is detected.
2.4.3.1.5 Enable condition
- system state is "drive"
- drive motor speed is within the operation range
2.4.3.1.6 Chart(s) and flow chart(s)
2.4.3.2 Drive motor phase current U/W sensors correlation rationality check (P0BFD)
The goal of this diagnosis is to detect an implausibility of phase sensor U in correlation with phase Sensor W.
2.4.3.2.1 Monitoring strategy
The peak to peak values of the sinusoidal current in phase U and V during one period has to be the same. In this diagnosis the peak to peak values of the current sensors are calculated and subtracted from each other. If the difference exceeds an upper or lower limit a drive motor phase current U/W sensors correlation rationality failure is detected.
2.4.3.2.2 Enable condition
- drive motor speed is within the operation range
2.4.3.2.3 Chart(s) and flow chart(s)
2.5 Phase U/V/W connection (P0C05)
2.5.1 Monitoring strategy
This diagnosis is implemented in the inverter hardware to monitor that all phase are connected. It will be monitored by an over current of the connected phases.
2.5.2 Enable condition
- drive motor speed is within the operation range
2.5.3 Chart(s) and flow chart(s)
