I've been trying to pin down my weak aircon problem which has led me to look at the HBV
The car has aircon but NOT Climate control. Here are the symptoms:
When air direction is on screen or feet vents and turn to cold the vents blow hot for about 30 seconds then lukewarm, never cold. If I select face vents - I get an icy blast.
I get similar with the aircon off, air is just that bit warmer.
o.k. so I thought the HBV has failed but before I condem it I thought I'd check the vac feed to it.
So here's what I did:
both heater controls to hot: no aircon
both to cold no aircon
repeat as above with aircon on
In each of the four cases there is absolutely no vac at the HBV. So then I thought, o.k. a vac line has dropped off/split etc: try blowing down it - result, the pipe appears blocked.
In addition to this my aux water pump (under coolant bottle) always runs - not sure if it should or is related.
I know that taking the heater controls out and the air dist unit can be an akward job so is there something else I should check before I go digging?