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Vehicle: 2025 Morgan Super Sports (CX / CX-V Platform, BMW B58 3.0L)
Location / Climate: High ambient temperatures (27°C–37°C)
Hi everyone,
I am reaching out to see if any fellow CX / CX-V platform owners (Plus Four, Plus Six, or Super Sports) have experienced an intermittent, heat-induced electrical failure of the interior cabin blower motor.
I am trying to determine if there is an official Malvern software/hardware bulletin or firmware patch for this issue.
The Symptoms & Diagnostic Proof:
1. Normal Driving (27°C+ Ambient):
During continuous driving at speed, the A/C and blower fan function perfectly. Even during a run where the dashboard temperature display reached 45°C, the blower fan operated without dropping out as long as the engine remained running and moving.
2. The Failure Trigger (Stationary Engine-Off Heat Soak):
If the engine is switched off and left parked for 30–60 minutes in high ambient heat (27°C–37°C), heat radiating off the BMW turbo engine bleeds directly into the bulkhead/firewall.
3. The Failure & Recovery Behavior:
Upon restarting the hot engine, the blower motor suffers a 100% total electrical loss (zero airflow). Even when ambient or dashboard temperatures remained high at 33°C–38°C, the blower fan eventually came back to normal operation during driving—leading to the suspicion that road vibrations played a role in re-establishing a thermally disrupted electrical path.
4. The Controlled Experiment:
During a 15-minute idle stop, the dashboard temperature display spiked from 33°C to 45°C. By propping open the right-hand side of the louvered bonnet to let trapped bulkhead heat escape, the blower system remained 100% functional throughout. This confirms that active ventilation around the bulkhead prevents the lockout, whereas trapped engine-off heat triggers it.
5. Remote Door Lock/Unlock Controller Failure:
Additionally, you cannot unlock or open the right-side door lock using the remote controller when this thermal distress occurs.
Dealer Action to Date:
My dealer consulted Morgan and replaced the MID-module (Body Control Module), assuming a defective component.
Outcome: The exact same behavior recurred on the very next hot day.
Conclusion: The MID-module itself is not defective. Rather, static under-bonnet heat soak causes the module (or blower speed controller/relay/harness connection) to exceed its internal thermal safety threshold during its key-on diagnostic self-test, triggering a hard lockout until cooling airflow and road vibrations restore the circuit.
Questions for the Forum:
1. Has anyone else running a CX / CX-V generation car in warm climates experienced a total loss of the blower fan following hot engine-off heat soak?
2. Is anyone aware of an official factory solution from Malvern—such as a post-shutdown electric fan run-on software update, revised firewall thermal shielding, or an updated higher-temperature-rated control module/resistor/harness?
3. Has anyone successfully escalated this specific BCM thermal boot-up lockout to Morgan Technical Engineering?
Any insights, technical bulletins, or advice on factory escalation paths would be greatly appreciated.
Thank you!
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