Symptoms
Heater always blows hot, or never gets warm even when the engine is hot.
Likely cause
A seized heater valve, a snapped control cable, or flaps in the heater box that have stuck.
Suggested fixes
Listed roughly in the order most owners try them.
- 1
Free off or replace the heater valve
Check the valve moves fully when the control is operated. Replace it if seized.
- Difficulty:
- Easy DIY
- Cost:
- £ (Under about £50 in parts)
- 2
Replace the control cables
Cables snap or slip at the clamp. Make sure the outer cable is clamped firmly at both ends.
- Difficulty:
- Moderate DIY
- Cost:
- £ (Under about £50 in parts)
This is general guidance gathered from owner experience and workshop practice, not a substitute for a workshop manual or a qualified mechanic. Costs are rough parts-only guides. Brakes, steering and suspension work affects safety, so if in doubt have it checked professionally.
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