VOLVO
IGM-U1A4B62 - Control Module Processor B. Algorithm Based Failures. Signal compare failure
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) compares the calculated torque with the requested torque. If the difference becomes too large, the code is stored. The fault is only checked once the combustion engine is running.
Possible causes
- Software fault in the IGM
- Internal fault inside the ISC voltage converter
What you can do
- 1Read out and clear the code, road test with the engine running and see whether it returns
- 2If you have diagnostic equipment: compare the calculated and requested torque in live data with the engine running; they should follow each other
- 3Have a workshop check whether new software is available for the IGM and install it if needed
- 4The high voltage system may only be handled by a workshop; do not work on it yourself
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.