Heater

[morgie]

Hi LAA69 - was there any update on this for you?

I seem to have a similar issue. Strange thing is that I can feel some heat (certainly not what I'd call "hot") on the passenger side whereas driver's remains cool even when set to the maximum hot temp. I'll go over some of the other troubleshooting points in this thread, I know my fan definitely kicks in.

[molveees]

Hi,

I have a 2002 Corolla T-Spirit, a few weeks ago, I noticed when setting the heater temp to "HOT" - the temp of the air seems to be more "warm" rather than what it used to be. This model has the digital climate control. I've checked the coolant (previous topics seem to check this first here) - this was not low, but have topped up never the less.

I would really appreciate any suggestions on what I can do / look for next.

Thanks,

You checked the coolant level, good. thats the 1st thing i would have checked. Has your car ever had a water leak? i ask because people try that radweld stuff that knackers & blocks the cooling system. If not you can move on.

Now Focus on the rubber hose Pipe on top of the radiator that disappears towards engine block. Start the engine from cold & monitor the temperature of this hose. If it gradually warms up then you have an open themostat, like mine. you will see this within 10-15 minutes of running the engine at idle speed.

What happens is thermostat remains shut until water reaches 82 degress. then thermostat opens, release hot water through the pipe on top of radiator (which you'd be touching & felling it go warm suddenly as water gushes in to the pipe), & cool water enters the engine block through the hosepipe at the bottom of the radiator.

Also look at the firewall of the engine where 2 smaller diameter rubber hose pipes are joined to the aluminium pipes of the heater core matrix. They should be equally warm otherwise that could suggest a blockage at the core.

Read other email in this topic. there is good information from other users too.

[molveees]

Hi LAA69 - was there any update on this for you?

I seem to have a similar issue. Strange thing is that I can feel some heat (certainly not what I'd call "hot") on the passenger side whereas driver's remains cool even when set to the maximum hot temp. I'll go over some of the other troubleshooting points in this thread, I know my fan definitely kicks in.

by "FAN KICKING IN" I assume you mean the cooling fan installed under the bonnet, when the water heats up to a specific temperature. One thing i'd say. Blockages, or air bubbles are rare on Corolla coolant systems as long as they have been drained & refilled according to the service schedule.

can you hear the motorised valve move when you change the blower temperature from low-high? you should be able to hear a motorised sound coming from under the steering. 1 thing i'd definitely check is the wire that connects to the diverter/damper valve. Its easy to get to. check my other post within this topic.

[s.illes79]

I don't wanna start a new topic so I ask it here.

I only get hot air if the engine is warm even if the AC is on. I had other cars before could heat up air before the engine was warm. Is is "bug" or "feature" ?

[molveees]

I don't wanna start a new topic so I ask it here.

I only get hot air if the engine is warm even if the AC is on. I had other cars before could heat up air before the engine was warm. Is is "bug" or "feature" ?

This is standard. Air only warms up when the coolant running through the engine & heater matrix warms up to engine temperature. If you are getting hot air even with AC i reckon you are gassed out & need to top up that R134a refrigerant gas.

[LAA69]

Hi LAA69 - was there any update on this for you?

I seem to have a similar issue. Strange thing is that I can feel some heat (certainly not what I'd call "hot") on the passenger side whereas driver's remains cool even when set to the maximum hot temp. I'll go over some of the other troubleshooting points in this thread, I know my fan definitely kicks in.

Update as requested:

Car still in Mr T, yes that will be 1 week come tomorrow morning LMAO, basically i dont think they have a clue beacuse they said yesterday, they were waiting for a Rolla with the same Heater etc to come in so they could try parts to see what works .... im PMSL, glad im not paying for this diagnosis.

So i still have the 1.3 Yaris courtesy car, which is gutless but at least i have wheels and am putting mileage on their motor. Phoning shortly to see if any progress has been made. :D

[Mick24]

They prob dont want to fork out for a new heater matrix tbh.

If you want to check the operation of the hot/cold servo motor - you can see it on the drivers side of the heater unit (to the left of the clutch pedal).

Set the heater to max hot and then remove the servo motor and see if you can move the diverter linkage any further to the hot side - chances are you wont.

Mick

[FoxX]

Update as requested:

Car still in Mr T, yes that will be 1 week come tomorrow morning LMAO, basically i dont think they have a clue beacuse they said yesterday, they were waiting for a Rolla with the same Heater etc to come in so they could try parts to see what works .... im PMSL, glad im not paying for this diagnosis.

So i still have the 1.3 Yaris courtesy car, which is gutless but at least i have wheels and am putting mileage on their motor. Phoning shortly to see if any progress has been made. :D

Thanks for the update Bud, very keen to see what the issue is. Dont go paying them any more, you could argue that you didnt need any of that other work done and yet you've paid for it and they had not correctly fixed the problem in the first place. They shouldnt have even given it back to you in a non working state to start with.

Just hope they dont start taking apart some poor sods t sport or t spirit to test parts in your car hehe, i'm sure they were referring to one of their own motors :D Fair doo's Mick, you know your stuff.

[LAA69]

Ok further update, gotta LMAO...

Spoke with them about an hour ago and apparently the problem lies with the "Aircon Amplifier" whatever that is ?

When i asked what this does, the response was ?????? yep "To be honest, i don't know" well i guess honesty is better than Bullsh17, ill find out more when i collect car.

Fault confirmed by swapping out one from this "Other Rolla".

Price for new Amplifier is either £170 or £220, there is 2 types, isn't there always 2 types? LOL

Talking of collecting car, part is on back order, so im stuck with the 1.GUTLESS Yaris until at least Weds next week, still, at least i have wheels and am putting mileage on their car .........

Perhaps ill just get my Altezza sooner rather than later ...... hmmmmmmmmm

My faith in Mr T is diminishing fast.........

[morgie]

can you hear the motorised valve move when you change the blower temperature from low-high? you should be able to hear a motorised sound coming from under the steering. 1 thing i'd definitely check is the wire that connects to the diverter/damper valve. Its easy to get to. check my other post within this topic.

Thanks molveees. Yes, I can hear the motorised valve moved when I change the blower temp from max cold, as I move up from that I can hear it for a few seconds. It's not continuous though as I move all the way up to max hot. Is that normal? With regards to the wire that connects to the diverter/damper - I saw you mention this in your last post, but I'm not clear on where this wire actually is? Sorry if I'm missing something obvious, but any pointers would be appreciated.

Update as requested: ....

Thanks for the update LAA69 - I'll continue to watch for your next post. Let's hope your faith can be restored, along with some heat!

[Mick24]

Ok further update, gotta LMAO...

Spoke with them about an hour ago and apparently the problem lies with the "Aircon Amplifier" whatever that is ?

When i asked what this does, the response was ?????? yep "To be honest, i don't know" well i guess honesty is better than Bullsh17, ill find out more when i collect car.

Fault confirmed by swapping out one from this "Other Rolla".

Price for new Amplifier is either £170 or £220, there is 2 types, isn't there always 2 types? LOL

Talking of collecting car, part is on back order, so im stuck with the 1.GUTLESS Yaris until at least Weds next week, still, at least i have wheels and am putting mileage on their car .........

Perhaps ill just get my Altezza sooner rather than later ...... hmmmmmmmmm

My faith in Mr T is diminishing fast.........

Can see why your faith in them is going out the window - just hope they have diagnosed it right this time

I always thought the AC Amplifier was to sense the speed of the aircon compressor compared to the engine rpm and prevent compressor lock-up - cant see how this would give you a lack of heat on the 'hot side' of the heater unit ( but i do stand to be corrected on that if anyone knows otherwise ).

Dont see why you should have to pay for the part either seeing as you are already £*** out of pocket and still have the original fault.

Mick

[molveees]

can you hear the motorised valve move when you change the blower temperature from low-high? you should be able to hear a motorised sound coming from under the steering. 1 thing i'd definitely check is the wire that connects to the diverter/damper valve. Its easy to get to. check my other post within this topic.

Thanks molveees. Yes, I can hear the motorised valve moved when I change the blower temp from max cold, as I move up from that I can hear it for a few seconds. It's not continuous though as I move all the way up to max hot. Is that normal? With regards to the wire that connects to the diverter/damper - I saw you mention this in your last post, but I'm not clear on where this wire actually is? Sorry if I'm missing something obvious, but any pointers would be appreciated.

Update as requested: ....

Thanks for the update LAA69 - I'll continue to watch for your next post. Let's hope your faith can be restored, along with some heat!

Hi You will need to remove the Panel Under the steering column directly above the pedals. This is held by 2 philips screws. Once its off you can access the matrix & the diverter. you will also be able to see a cable running down from the diverter & disappearing down behind the carpet edge in front of you. This cable connector is easy to spot. you cant miss it. If you can hear the sound of the motor it may not be the cable unless its half-plugged in so it may be an idea to unplug it & plug in back again. & Yes! The sound is correct. the movement is incremental, not continuous.

[morgie]

Thanks molveees. I should be able to take a look this weekend, will post an update.

[morgie]

Right, I checked the cable under the steering column as suggested - it seemed fine. I disconnected and reconnected it anyway, can you confirm this is the correct one (see below). I'm not too confident in going much further with the matrix without having a better idea of what I'm doing.

I'd been out in the car, ~10 miles and checked under the bonnet. The radiator didn't feel that hot, it wasn't burning me to carefully touch it. There was definite heat from the top pipe shown here (directly to the left of the battery):

The pipes leading back into the cabin (if I have the correct ones?) also felt like they had some heat, the right one being hotter from memory:

Any other pipes in particular that I should be checking, or any other thoughts from this?

Thanks again for all the help so far molveees, appreciate any further thoughts you or anyone else may have.

[LAA69]

You may well have the same problem as me fella ......

[morgie]

Good to know it may not just be you/or me. Anything else I could check myself LAA69 to confirm if it's exactly the same symptoms as you have? Do you know when the "Aircon Amplifier" will arrive (fingers crossed for it....although I'm not loving the prices)?

[LAA69]

Good to know it may not just be you/or me. Anything else I could check myself LAA69 to confirm if it's exactly the same symptoms as you have? Do you know when the "Aircon Amplifier" will arrive (fingers crossed for it....although I'm not loving the prices)?

It should be in around Weds this comming week, i have everything crossed.

If both your inlet/outlet pipes to the Matrix are hot and you can hear your vents moving when adjusting the temp, then it sounds the same problem, as all apeared well with mine except air was just luke warm.

Now as for diagnosing this, i wish i could help you but even Mr T found the problem by swapping out parts as opposed to actually fault finding, which is why my faith in them has gone.

When i collect my Rolla, i will ask for more details on this Amp, then ill try posting an explanation on here, one of us may come up with a way of a better diagnosis. Worth a shot.

Soz fella, will keep posted ..... good luck.

[morgie]

No problem, I will wait for your update. It'll be great if it does work and they can provide a further explanation. Be nice to know if the £170 one does the job....odds on them using the £220 one? :D

[FoxX]

Still convinced it’s a partially blocked heater matrix like Hogie had replaced a while back.

I definitely have the same symptoms, checked all pipes - they are roasting hot going into the matrix, stepper motor moves fine, full coolant (no leaks).

As Mick says, really don’t see how it could be this aircon amplifier. I found this article from 2002 which talks about it -!! Article !! It sounds like this amplifier will just shut off your A/C when it detects a problem with compressor / engine speed.

Naturally I will eat my words if they fix it. Dont drive it away until they can prove its working though, hopefully your engine will be warm when you arrive from the furious testing they will have been doing.

[LAA69]

Interesting read, i will ask for the Old Amp and post i pic if i can get it to show what it looks like, a Black Cig box ???

We will see .........

I wish i didnt have to say this but ...... More to follow .....

[Mick24]

My T Sport was suffering the same problem when i bought it - luke warm heat.

After checking the Pollen Filter,stat,coolant strength,water pump,heater controls/AC operation (even did a Cylinder Leakage Test to eliminate internal problems) - i reversed flushed the matrix.

Got a lot of small black round balls of crud out of it (although the coolant/rad/expansion bottle was 100% clean) which you could squash between your fingers and a few bits of solder laying in the bottom of the bucket.

Heater has been spot on since with nice hot air blowing out of it.

Mick

[morgie]

Hi Mick, sounds extremely similar. Could you explain the steps involved in reverse flushing the matrix? Thanks...

[LAA69]

If the Matrix has a blockage, would you not expect a difference in Temp between the inlet/outlet pipes ?

[Mick24]

Quite easy to do a reverse flush,

* With the engine cold - clamp off the flow and return hoses for the heater and then remove them from the bulkhead stubs.

* Find some suitable diameter hose (5/8" ??) and connect 2 lengths to the bulkhead stubs with jubilee clips.

* The right hand stub/temporary hose should drop into a bucket so you can see if anything flushes out.

* The left hand stub/ temporary hose connects to a hose pipe or pressure washer - I used my Karcher pressure washer to flush the matrix and seeing as the other end of the matrix is open/in a bucket, there is no chance of any pressure build up or damage to the matrix core.

* Flush until the bucket is full and check for debris in the bucket - repeat until no more debris is found ( took me about 5 flushes ).

* Disconnect the temporary hoses and refit the flow (right hand stub) and return (left hand stub) hoses - remove the clamps and check coolant level.

* Set the heater to Hot and start the engine - check flow and return hoses to make sure they are hot ( no airlocks ) and then take the car for a run.

If you had the same problem, you will now have a toasty warm heater :D

When i had the luke warm heat - i used to set the heater on Auto and 23 degrees, the blower would be on approx 5 bars constantly trying to heat the cabin.

After the reverse flush, the blower now drops down to 2 bars to maintain the 23 degrees.

Hope this helps

Mick

[molveees]

Just one caution to add to mick's reply. I assume you'd be using a garden hose to flush out debris. Do not ever connect the garden hose snug on to the outlet of matrix when reverse flushing. Rather get the Garden hose running first from a distance of about 50mm away from the matrix outlet & slowly bring it closer to the outlet port & wait until you see water flowing out of the other port. Now you can fit the hose to the outlet & purge it for as long as your heart's content. If there really was a stuuborn blockage & you were snug on to the matrix you'd actually blow a hole in the aluminium core & then you'd be in trouble-deep.

The whole idea is to avoid the build up of high pressure within the core. Hope you got my point.

2ndly Dont use a bucket for catiching the water otherwise you'd be too busy emptying it out. Catch the cooling only & once water only starts to flow out Use a Sieve instead to catch the debris & let water run down the harmlessly. If you catch rubber bits, surely some seals inside the system have disintegrated & a repair is imminent.

Now remember those rubber hosepipes will be stuck on to the aluminium core. Perseverence will be needed hear. Fairy liquid works particularly well to loose them up (good old trick from the text book). The hoses can take a fair bit of twisting but avoid twisting it too much & apply twists in both directions to work the fairy. clean the inside of the hoses before finally putting them back on.

btw are you losing coolant at all?

Let us know your findings & see if any of us can help you further.