VOLVO
IGM-B20062F - Electric Machine Temperature Sensor. General Electrical Failures. Signal erratic
System
Unknown System / Manufacturer Specific
Volvo models this fault code applies to
Applies to the following models:
1 modelV60 (2011–)
Show models by year and engine (2)
What does this fault code mean?
The high voltage generator control module (IGM) measures the temperature in the starter generator ISG using a temperature sensor. The code is stored when the signal from the sensor changes unreasonably fast, meaning the signal is erratic. The fault is only checked once the test has started at ignition on.
Possible causes
- Loose connections, contact resistance or oxidation in the terminals between the ISG and the voltage conversion unit ISC
- The signal cable is short-circuited to ground or to supply voltage
- Open-circuit in the signal cable
- The wiring between ISG and ISC is damaged
- The temperature sensor on the ISG is damaged
- Internal fault inside the ISC voltage converter
What you can do
- 1Read out, clear the code and start the car to see whether it returns
- 2If you have diagnostic equipment: follow the ISG temperature value in live data and see whether it jumps or changes erratically
- 3Have a workshop check the signal cable between the ISG and the ISC and its connectors for looseness, chafing or short circuits
- 4Do not work on the high voltage system yourself; have a workshop carry out those checks
Symptoms you may notice5
- Warning symbol and text message in the display
- Warning about power supply problems from the alternator and charge regulator
- Charging of the high voltage battery while driving is absent, reduced or not working correctly
- High voltage battery is discharged or charges poorly
- HYBRID drive mode: the combustion engine is active all the time or too often
What the fault can affect1
- The high voltage battery cannot be charged by the combustion engine
General guidance for car owners. Diagnosis on the car can point to a different cause.