The blower runs, yet the cabin stays cold in electric operation. Before treating that as a high-voltage heater failure, record the heating settings and the complete climate-control scan. Those details are central to a published Volvo technical journal.
What Volvo’s document says
Volvo Car USA journal US36257.5.2, dated 2 June 2023, addresses poor heating with permanent CCM fault U133A93 on its specified vehicle types and production ranges. It also says to check that the additional heater is enabled in the centre display, because disabling it can leave pure mode without heat. Read the Volvo journal.
This is a US-market technical reference. A UK vehicle needs its VIN, equipment and the latest applicable Volvo information checked; the document is not a promise of UK warranty coverage or a universal instruction to replace the heater.
Prepare the details before booking
Tell the workshop whether the concern affects electric driving, engine-running operation, preconditioning or all modes. Include the outside temperature and a photograph of the relevant settings if possible. Keep the code’s status as well as its number, and state which controller reported it.
For garages, attach the existing diagnostic findings and any software or heater-replacement history. Do not clear the report simply to see whether the code returns before preserving it.
High-voltage work needs an agreed assessment
The heater is part of a high-voltage system. Owners should not open it or attempt direct-power testing. Contact AXION about the heating fault so we can confirm support and the assessment route for the exact vehicle. Complete-vehicle work is by arrangement at Didcot.
Reviewed September 2026. Use the complete manufacturer-specific fault description and vehicle repair information.