Verso D4D 2.0 Heater problem

[boothy1]

Hello ,  Appreciate some technical help if anyone can .   Heater blowing cold , went from fine a few weeks ago to nothing suddenly , just cold air, not warm. In the 3 years ive had the car, heater has been very powerful and effective, but temp setting has always read higher than actual cabin temp, ie set to 25 degrees just to feel about 20ish. So I assumed it was the control panel, changed out today and I was wrong, same fault, so now looking at matrix, water flow control valve ( when I can find it !).  Coolant looks ok in reservoir, original pink long life, no leaks or loses at all, and car has been very well serviced generally but it may be that its original coolant , so if its 14 years old now, 115k miles, this could be the problem, sludge etc??

So I can just about get my hands on the bulkhead hoses to try to reverse flush the matrix , not sure about access to remove hoses and flush. But do you agree this should be my next step ?   I've took out the glove box to look into dash, can see main fan and flap diverter actuator, but cant see a flow control valve for the matrix, anyone know how I get to this, and how to change it ? it looks like hoses pass into bulkhead behind fan unit, so do I have to take out the fan etc ? Seems very crammed in !      Should I look at this first and is this likely to be the fault as it must be a motorised/ automated valve, but I don't know how to get to it  ?   Do I have to take out upper dash to gain access and if so is this straightforward ish as a home job, I know there's an air bag to be careful of, and found on line a drawing for standard corolla showing upper dash help in place by clips and two studs, so that looks do able, but not sure about the verso . 

I've got a recall from Toyota to change the passenger air bag which I need to book it into Toyota for soon.   Would it be sensible for me to ask Toyota Dealer to look at heating at same time if top dash has to be removed for air bag change? I'm a reasonable DIY er  but don't want to take on too much at home, especially without a manual on how to do it .   

Any ideas much appreciated ,   john

[Notoyboy]

Hopefully someone will be along who can reply more specifically, but with my very limited knowledge of the Verso, does it have analogue or digital heater controls?  If it's digital, then maybe it doesn't have a flow control valve at all, relying on the flaps to control the heat output.  Flaps have motors/gears, and maybe your problem lies there?

Not sure whether flow control valves are a relic of the past.  I remember them, as that's what cars were fitted with when I learnt to drive!

[boothy1]

Hello  Martin ,     many thanks for reply , much appreciated . 

Yes control is digital , and so you may be right,  might not be a flow control valve ,just flaps ?  

I can get to the flap above the fan and the small motor and linkage to that seem ok and moving, but flap above fan seems to be re circ flap , but cant find anything that regulates the heat yet ........may be deeper in the bowels of the dash ....... 

You can tell its a while since i've tried to fix a car heater !!  they were a lot simpler a few years ago, just a cable and valve ! !      many thanks again    John      

[boothy1]

A quick update ,

Appreciate tips from anyone who can help answer how I get to the Verso Heater Matrix and heater control flaps, question is does top of dsah need to come off and is it DIY doable at home ok?

Thanks to Martin,  I'm presuming no water flow control valve is fitted, its probably flap control on heater matrix. Problem is I cant see how to get to it . 

I've just checked (by hand ) temp of hoses at bulkhead and when engine is hot, both are quite hot , one maybe seems hotter than the other ( will check better with infra red heat gun soon when I can borrow from work)  so maybe no blockage, maybe a flap control issue. 

Appreciate any advice ,          thanks   John

 

 

 

[Stivino]

Assuming that you can divert the air between the screen, footwell and side vents, you can only be talking about the blend flap.

[boothy1]

Hello ,  and thanks yes, I can divert air , so its the blend flap I need to get to I believe, if anyone can help ,        many thanks for clarifying     John  

[Stivino]

What happens when you turn the heat up full, does it still blow cold air?

Also, have you checked that the wee air intake on the dash is clear? It’s just to the left of the steering column, if I remember rightly.

 

[oldcodger]

Hi,

Not sure what differences there are between the standard Corolla and the Verso,  but assuming they are similar and yours has the digital control as well, then there is no heater control valve, its just the flap that selects between the a/c evaporator and the heater matrix.

What you can do, is set the temp to cold, then hold the temp button down so it runs up to hot,  but listen for the flap motor, you typically here it about the 20 - 25c mark, which should indicate its running ok.

On the standard Corolla you can actually see the motor and gear running under the drivers footwell.

You could also test the other flaps,eg flow divert, screen , middle  and footwell and also the internal only flap.

Given they all sound ok , then would suspect its the matrix that becoming blocked, it seemed a common problem a few years ago on the 2002 model, so suppose 2005 is prone as well ?

If you search the forum there are a couple of very long thread on clearing the matrix, though I would start with a simple hose pipe back flush and see if it runs though ok,

Asking your local Toyota to look at it when doing the air back will still cost you an arm and a leg ! imho

 

[boothy1]

Yes constant ambient air with all settings of fan, air con cooling is working ok,   thanks  John

[boothy1]

Many thanks  for past two tips , very much appreciated ,  will listen for flap moving (or not ) at around 25 degrees as you say, can hear, see , feel ,  all other diverters working fine .   

Will have a look again under the foot well this week end  and access to bulkhead for flushing ,  I agree with asking Toyata dealer , its not something I'm keen on as cant afford main agent hourly rates !!!     many thanks  again really appreciated

 

[oldcodger]

If I remember correctly from those previous Corolla Heater threads,  a standard 1/2" garden hose and some jubilee clips should attach to the matrix pipes ok.

You will then have to see how readily it flows out,  no something I have done, so can not say how strong the flow should be.

They have used a variety of compounds to clear most blocked ones, though expect some will have to be replaced, but seems you are looking a quiet a price and second hand ones a very pot luck way to fix things,

Again, seem to remember those thread detailing how to remove the matrix,  think it was from the side, and not needing to remove the whole dash etc, so do look up those threads and alos on Ytube as these are some showing the matrix being replaced.

When all done, sounds like you need to replace you coolant and give things a flush, when doing so, if using concentrate coolant, ensure you use Deionized water, hard water or not flushing can cause it to block quicker.

Here is one of those long thread I mentioned  -  https://www.toyotaownersclub.com/forums/topic/76133-heater/page/6/#comments

 

[boothy1]

This is all great advice, and great links,  many thanks codger, stivino, martin,    I will post how I progress over the next week or two,   many thanks      john  

[boothy1]

Thanks for your help,

I found was  the heater flap was stuck closed ,  thought actuator was broke, removed it , tried it loose and it was working , moved flap about manually, refitted actuator and working fine (for now). I guess actuator might be on the way out so will look out for a spare. 

Actuator is fiddly to remove, above clutch pedal, under bottom of dash, two screws hold it in place. 

I first flushed the matrix with garden hose, found it fine not blocked at all, coolant all very clean, no problems there, just flap problem.

whilst checking pollen filter and air recirc flap actuator, managed to break it (duh!!) luckily its stuck in fresh air position. I cant easily get to the actuator to fix what I've broke!!.  Looks like if you can remove the fan and motor , the flap and actuator can be accessed. Fan motor and flap look very crammed in under dash, not sure if its worth the time trying to fix it, if anyone has removed this appreciate if they can let me know how easy this is ,        thanks      John