Just replaced one today. Simple test is to remove the power connector from the valve - this should open the valve & give full heat. Beware the plastic parts of the valve become brittle with age and are easy to break. You need to bleed out the air afterwards - with a COLD engine, remove the pressure cap from the expansion tank & run for 2min MAXIMUM, topping up expansion tank as required, then replace the cap.
Handy Spanner
January 2010
yes definately second that. cost you about £25 for the part.
focusfh56
December 2009
power to the heater control valve is a pulsed feed depending on heater dial position (noid test light needed)heater control valve most likely faulty very very common ,it is mounted on top of bulkhead panel in centre 4 hoses attached.not repairable sealed unit.easy job!
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