VOLVO
IEM-U1A4B61 - Control Module Processor B. Algorithm Based Failures. Signal calculation 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 electric rear axle drive module (IEM) compares the speed of the electric rear axle ERAD with the speed requested at idle. If they do not match, the code is stored. The fault is only checked once the car is driven in gear D or R.
Possible causes
- Software error in the electric rear axle drive module (IEM)
- Internal fault inside the ISC voltage converter
What you can do
- 1Read out, note and clear the code, then road test in D or R to see whether it returns
- 2Have a workshop check whether new software is available for the control module and install it if needed
- 3If you have diagnostic equipment: compare the measured ERAD speed with the requested speed in live data while driving; they should follow each other without large differences
- 4Do not work on the electric rear axle or its high voltage system yourself; have a workshop carry out those checks
Symptoms you may notice4
- Warning symbol and text message in the display
- PURE drive mode disengages by itself or is not available
- AWD drive mode disengages by itself or is not available
- HYBRID drive mode runs with the combustion engine active all the time or too often
What the fault can affect2
- Electric propulsion is not possible
- Brake energy recovery from the electric rear axle ERAD is not possible
General guidance for car owners. Diagnosis on the car can point to a different cause.