VOLVO
IGM-U1A4B93 - Control Module Processor B. Component Failures. No operation
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?
Although the code indicates that something does not work, it applies when the control module's communication is disturbed or missing. The high voltage generator control module (IGM) monitors its internal components and related functions. The fault is only checked once the test has started at ignition on.
Possible causes
- Software fault in the IGM
- Internal fault inside the ISC voltage converter
What you can do
- 1Read out, clear the code and start the car to see whether it comes back
- 2Have a workshop read the control module with diagnostic equipment and update the software if needed
- 3If the fault returns, have a workshop check the ISC voltage converter
- 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.