Cold air from one side? Fix the flap, not the whole heater box.
DIY repair kits for the known heater-flap fault in MINI (2014–2021) and BMW (2016–2021). Fitted through the footwell trim – no dashboard removal.
- 400+ kits sold
- Step-by-step guide included
- Ships from Denmark
Which fix do you need?
Remove the flap actuator (two screws) behind the footwell trim and turn the shaft gently by hand. How far it turns tells you what is broken.
Broken stops
The plastic end stops inside the heater box have cracked, so the actuator fails its calibration and gives up – usually leaving one side stuck on full cold or full hot.
Broken shaft
The shaft has snapped and no longer moves the mixing flap. You drill an access hole with our guide and fit a new shaft and stop insert.
Right-hand side only for now – contact us about the left-hand side.
The dealer replaces the whole heater box. You don’t have to.
- New heater unit (per BMW/MINI service bulletin)
- Dashboard has to come out
- Owners on forums report bills of £2,000+
- Kits from 300 kr
- Fitted through the footwell trim
- Basic hand tools, plus a diagnostic tool to clear fault codes
Does it fit my car?
These are the models listed in the official BMW and MINI service bulletins for this fault.
MINI
SI M64 02 21- Cooper2014–2021
- Cooper S2014–2017, 2019–2021
- Cooper SE2021
- Clubman2017
- John Cooper Works2018, 2021
BMW
SI B64 06 21- i3, i3s (incl. Range Extender)2016–2021
- 228i / M235i Gran Coupe xDrive2016–2021
- X1 sDrive28i / xDrive28i2016–2021
- X2 sDrive28i / xDrive28i / M35i2016–2021
All kits and tools
For broken stops
Reinforced stops and longer screws. Parts marked L / R, so one kit covers either side.
For a broken shaft
Right-hand side · needs a 29 mm (1 1/8") hole saw
Drill guide, 29 mm hole saw, replacement shaft and stop insert.
Drill guide, shaft and stop insert. Buy the hole saw locally and save on shipping.
Replacement shaft and stop insert, for when you already have the drill guide and hole saw.
Tools
How the stops repair works
- 01 Remove trim and actuator Ignition off. Unplug the actuator and remove its two screws.
- 02 Check the shaft Turn it by hand and note the position for the temperature you want.
- 03 Fit the reinforced stops Mount the new stops from the kit on the heater box.
- 04 Refit and clear codes Refit the actuator with the longer screws, then clear the fault codes with a diagnostic tool.
Questions
Is this an official BMW / MINI part?
No. Heater Fix is an independent aftermarket repair. BMW and MINI know about the fault (service bulletins SI M64 02 21 and SI B64 06 21), but their fix is replacing the complete heater unit.
Left or right side – which kit do I need?
The Heater Fix Kit works on both sides (parts marked L and R). The Stop Repair Kit and the Broken Shaft kits are for the right-hand side. Contact me for Left-hand side broken shaft.
How do I know if the stops or the shaft is broken?
Remove the actuator and turn the shaft by hand. If it stops at its end positions, the stops are the problem. If it turns more than 70°, the shaft is broken.
What tools do I need?
Basic hand tools to remove the trim and actuator, and a diagnostic tool to clear the fault codes afterwards. The broken shaft repair also needs a drill and a 29 mm (1 1/8") hole saw.
How fast do you ship?
I normally ship next working day