Heater Problems

[clackie]

Anyone had any break throughs on this? Im having the same problem with my type s

 

[muddym2002]

Anyone ever fixed this issue on the type s?

Thanks

 

[freddofrog]

Ive got the same issue on my type s. Hot air on passenger side but cold on drivers side. Raised it on here a few years ago but no one had any idea what the problem could be. gave up trying to get it repaired as no one had any idea what the issue was :-( Will be interesting to see if a solution can be found

Anyone ever fixed this issue on the type s?

Thanks

If you've not got it set to DUAL then it's probably an issue with the motorised flaps on the driver's side.

The system works by mixing cold air with hot air from the heater matrix. If you're getting heat on one side then you can ***ume that the heater matrix is working ok, which mean that the motorised flap is stuck on the driver's side, so that you're only cold air

The other possibility is that the temperature sensor is faulty, there's a thread on here somewhere about the sensor, where it is and how to test it.

 

[freddofrog]

here's the thread

http://typeaccord.co.uk/forum/topic/18348-drivers-vent-always-hot/


the Honda Service Manual on DVD gets mentioned in that thread, I have the DVD as well and I looked on that DVD and found the info, I'll try and get a screen-shot

 

[freddofrog]

a couple of screen shots which may be of use

note where it says that these images are LHD car, the RHD car is symmetrical

IMO it all depends on how well the temperatures work in DUAL MODE as to whether or not it's the evaporator temperature sensor that is the problem, or the motorised flap(s)

 

[freddofrog]

There is also a guide on the Honda DVD for trouble-shooting the aircon system

I have created some images from the guide (click on an image to make it full size)


One way is to use the Honda HDS

If you don't have a Honda HDS there is also this method

and finally, the best could be this

 

[muddym2002]

Appreciate the help freddofrog

 

[freddofrog]

There is also a guide on the Honda DVD for trouble-shooting the aircon system

I have created some images from the guide (click on an image to make it full size)




and finally, the best could be this

My Accord is SORN and under a car-port at the back of my house, with the battery negative disconnected.

I just went out and tried the above, and wow it is absolutely fantastic !!!!!

It's a "toy" on the car in its own right !!!!

 

[muddym2002]

My Accord is SORN and under a car-port at the back of my house, with the battery negative disconnected.

I just went out and tried the above, and wow it is absolutely fantastic !!!!!

It's a "toy" on the car in its own right !!!!

Lol ive just tested the temperature sensor and everything seems ok. Didnt get any error messages. Is is safe to ***ume the issue is the motorised flap? How do I go about repairing it? Once again thank you freddofrog for your ***istance

 

[freddofrog]

what did you get for each readout ?

I'll do a comparison with mine (need to go out and do it again and write it down)

 

[muddym2002]

I've misplaced the findings but none of the sensor showed the error message so ***umed sensor was ok. Can go out and do it again

 

[freddofrog]

I went out about an hour ago, took some readings, then started the engine. Left it running for half an hour (car is round the back of the house under a car-port, so no chance of it being nicked) and took some more readings. Changed the heater settings with it still running, left it for a further half an hour, then took some more readings, and switched off.

Initial readings

1 in-car temp .... 08
2 ambient ......... 09
3 solar light ....... 01
4 engine coolant 09
5 evaporator temp 07
6 drivers air mix % 98
7 passenger mix % C9
8 car speed ......... 00
9 vent temp air out 98

obviously 7 and 9 are bogus readings

note that you can go into the A/C manual controls (menu on the satnav on the Exec car)
I set A/C to off (i.e. no compressor)
Also the buttons work (don't press Auto or the trouble-shooting stops and you'll have to switch off to start again).
I made sure that DUAL was OFF

half an hour later

1 in-car temp .... 21
2 ambient ......... 09
3 solar light ....... 01
4 engine coolant 85
5 evaporator temp 17
6 drivers air mix % 26
7 passenger mix % 27
8 car speed ......... 00
9 vent temp air out 30

I then set DUAL to ON and played with the temperature buttons (you can't see the temperature settings because the toruble-shooting uses the display)

1 in-car temp .... 21
2 ambient ......... 09
3 solar light ....... 01
4 engine coolant 86
5 evaporator temp 17
6 drivers air mix % 77
7 passenger mix % 28
8 car speed ......... 00
9 vent temp air out 61

I then witched DUAL OFF and ramped up the temperature setting (again, not displayed) and left it for another half hour

1 in-car temp .... 28
2 ambient ......... 09
3 solar light ....... 01
4 engine coolant 88
5 evaporator temp 19
6 drivers air mix % 64
7 passenger mix % 63
8 car speed ......... 00
9 vent temp air out 47


From that, I can tell that everything in my car is working !!!

For anyone reading this in future, try the same to check out the sensors, controls, and the motorised flaps

 

[muddym2002]

Cheers for the readings. Any idea how do I go about changing the motor on the flaps? Anyone on here done it before?

 

[freddofrog]

Here is a similar image from the Honda DVD as the one in post #35, but it has more info on it (btw if you click on pics in the forum they go full size)
Note that it is a LHD image again, RHD is symmetrical

When I click on the blue links in the original html image, it takes me to the various relevant guides. The air-mix motors and flaps are on the heater core, and to access that you have to remove the complete centre console and dash, which has many pages and diagrams.

I don't think anyone on this forum has ever removed the complete centre console and dash, in all the other threads where this problem has arisen, I think they have decided to leave it when the prospect of removing the console/dash is mentioned.

 

[muddym2002]

Thanks for all the input mate. Much appreciated

 

[wahabishtiaq]

Fred are you alright?


This much research, mate I award you with best research ever done on any car aircon.

Amazing!!!

 

[freddofrog]

It's an unknown toy in the car :lol:


btw, for aircon itself, you might want to read this too
http://typeaccord.co.uk/forum/topic/10382-diagnosing-aircon-problems/

 

[JapCar]

Hi freddofrog, My problem is that cold air is blowing just from passengers vents, from drivers ones blowing just normal temperature air. (2007 EX 2.2 i-CTDi)
I saw your test readings and tried to compare to mine but can't understand some things...
Just to say you have 9 sensor readings, I've got 10 readings (the last one is A/C Pressure Sensor)
Here are readings about 30 minutes after car was running with AC OFF.
Immediate readings after ran the engine:
1 in-car temp .... 26
2 ambient ......... 14
3 solar light ....... 40 to 70 (changing)
4 engine coolant 35
5 evaporator temp 18
6 drivers air mix % C9 (???)
7 passenger mix % 1 to 2 (changing) (???)
8 car speed ......... 00
9 vent temp air out A1 to A5 (changing) (???)
10 AC pressure 06 (MPa)

Here (few days later) are readings immediately after the car was running with AC ON :
Engine is running:

1 in-car temp .... 31
2 ambient ......... 21
3 solar light ....... 27
4 engine coolant 81
5 evaporator temp 20
6 drivers air mix % C9 (???)
7 passenger mix % 00 (???)
8 car speed ......... 00
9 vent temp air out C0/b9 (changing) (???)
10 AC pressure 10 (MPa) ..... (03 when AC is OFF)

Would you explain something about 6, 7, 9 and 10 ?

When compressor is running, on the glass window i see turbulence, not smooth stream with a little bubbles as requires.

 

[freddofrog]

^ I've just seen this, but on my way out at the moment, I'll reply later

 

[freddofrog]

Right, I've read through your post properly and

6th reading ... I did think that C9 is a bogus reading. In my post #42, when I initially went into this diagnostic thing with the engine not running, I had C9 in the 7th reading (passenger side). But I now think that C9 means 100% i.e. the vent is in the position such that it only lets warm air into the ducts.

7th reading ....***uming that DUAL was OFF, I would say that the passenger's vent is stuck in the position such that it only lets cold air into the passenger's ducts (7th reading correlates with the fact that only cold air is blowing through that side).

9th reading .... If you look at the last picture in post #36, there is a conversion table. A1 = -1. A5 = -5, B9 = -19, C0 = -20. There is no way that those reading are correct, so the temperature sensor on the main vent is probably faulty

10th reading ... it looks like the compressor is working, but having said that, I would have expected the evaporator temperatures (5th reading) to be lower than those readings. Maybe the evaporator temperature sensor is faulty, or maybe the condenser (in front of the engine radiator) is perished (weak ability to allow heat out of the aircon system)

 

[JapCar]

I am confused what and how to check...


For 9- There is no way that those reading are correct, so the temperature sensor on the main vent is probably faulty. Which is this sensor on picture from post #44

For 10- I would have expected the evaporator temperatures (5th reading) to be lower than those readings. My readings are just 1 deg. less than yours...??
- Maybe the evaporator temperature sensor is faulty I see where the sensor on the picture is.
- the condenser (in front of the engine radiator) is perished (weak ability to allow heat out of the aircon system). I know where the condenser is but what physically means "perished" and how to check it?

Generally, is there any guide / thread how to access vents and sensors (to check them) from picture in post #44 ?

 

[freddofrog]

For 9- There is no way that those reading are correct, so the temperature sensor on the main vent is probably faulty. Which is this sensor on picture from post #44

good question, of the 5 temperature sensors in the readings, you're right., it's not in the diagrams in this thread
- in-car temperature (1st in the list) ...shown in the diagram in #44
- ambient (2nd in the list) ....not shown in the diagram, but it is external, IIRC down under the front bumper
- engine temperature (4th in the list) ...speaks for itself
- evaporator temperature (5th in the list) ...also in the diagram in #44
- vent temp air out (9th in the list) ...this is the one we're talking about, I have seen it in another thread, but at the moment I can't remember where

For 10- I would have expected the evaporator temperatures (5th reading) to be lower than those readings. My readings are just 1 deg. less than yours...??

I had A/C OFF i.e. compressor not running

For 10- I would have expected the evaporator temperatures (5th reading) to be lower than those readings. My readings are just 1 deg. less than yours...??
- Maybe the evaporator temperature sensor is faulty I see where the sensor on the picture is.
- the condenser (in front of the engine radiator) is perished (weak ability to allow heat out of the aircon system). I know where the condenser is but what physically means "perished" and how to check it?

"perished" means that many of the vertical elements between the horiontal cooling fins have disconnected or fallen out of the condenser, see my one before I replaced it http://typeaccord.co.uk/forum/topic/10382-diagnosing-aircon-problems/?p=187690

Generally, is there any guide / thread how to access vents and sensors (to check them) from picture in post #44 ?

they've been mentioned in a couple of other threads
- to get to the evaporator, remove the glove box, then the blower unit, and the evaporator can then be accessed
- one of the other sensors (vent temperature I think) is also in the thread I'm thinking of, I'll have to find it

 

[JapCar]

good question, of the 5 temperature sensors in the readings, you're right., it's not in the diagrams in this thread
- in-car temperature (1st in the list) ...shown in the diagram in #44
- ambient (2nd in the list) ....not shown in the diagram, but it is external, IIRC down under the front bumper
- engine temperature (4th in the list) ...speaks for itself
- evaporator temperature (5th in the list) ...also in the diagram in #44
- vent temp air out (9th in the list) ...this is the one we're talking about, I have seen it in another thread, but at the moment I can't remember where




I had A/C OFF i.e. compressor not running






"perished" means that many of the vertical elements between the horiontal cooling fins have disconnected or fallen out of the condenser, see my one before I replaced it http://typeaccord.co.uk/forum/topic/10382-diagnosing-aircon-problems/?p=187690





they've been mentioned in a couple of other threads
- to get to the evaporator, remove the glove box, then the blower unit, and the evaporator can then be accessed
- one of the other sensors (vent temperature I think) is also in the thread I'm thinking of, I'll have to find it

- to get to the evaporator, remove the glove box, then the blower unit, and the evaporator can then be accessed On this way access will be just at one side of the evaporator... but sensors, motors are at both sides. Probably central console as well?

- one of the other sensors (vent temperature I think) is also in the thread I'm thinking of, I'll have to find it OK

 

[freddofrog]

- to get to the evaporator, remove the glove box, then the blower unit, and the evaporator can then be accessed On this way access will be just at one side of the evaporator... but sensors, motors are at both sides. Probably central console as well?

I think you are correct, the evaporator sensor is actually on the right-hand side of the evaporator, see next

- one of the other sensors (vent temperature I think) is also in the thread I'm thinking of, I'll have to find it OK

I've done a "drains up" on this, and I've come to the conclusion that the "vent temp air out" sensor is not anywhere on any Honda parts drawings, nor on the Honda DVD, nor has it been mentioned in any other threads in TA. The temp sensors that have been previously mentioned in other threads (which I've found and don't need reference here) are the in-car temp sensor, and the evaporator temp sensor.

Something that has always puzzled me as well, is that there must be separate temp sensors for each side, otherwise it would not be possible for the "mix flap" motors to know their target mix %.
My conclusion is that there must be temp sensors in the controllers for the "mix flap" motors. If that conclusion is correct, then I also conclude that the "vent temp air out" sensor is also in one of the control units (it clearly exists, because there are readings coming from it in the list).


For completeness, here is what I have found (click on image to enlarge it)

Honda parts drawing for main heater

5 = heater
6 = mode motor
7 = driver mix motor
8 = passenger mix motor
16 = evaporator
22 = thermistor (evaporator temp sensor)


Honda parts drawing for other heater sensors

1 = light sensor
3 = ambient temp sensor
4 = in-car temp sensor (although two positions shown, only one is fitted, depending on LHD or RHD)


Circuit diagram of the heater system

larger zoom into area of the circuit diagram

 

[JapCar]

Everything very complicated...
On the last picture bottom left I see a transistor, probably the same one is on the picture from post 44 (Power transistor)..I wonder what is it for?

 

[freddofrog]

if you look at the image second from last (of the complete circuit), that "power transistor" is internal in the "climate control unit" (which is shown as a large block on the complete circuit digram). So that "power transistor" just symbolises that the "recirculation control motor" can be switched forwards or backwards (so that recirculation is either on or off).

There is a part called a "power transistor" which is item 11 in the top image in #54 (and also shown in #44 as you say), but that is for turning the heater valve on or off, via the cable which is item 12 in the top image in #54.

 

[JapCar]

OK. Thanks! I'll carry on investigation...

 

[JapCar]

To remind my problem- passenger side AC blew cold (about 8-9 deg), driver side blew ambient temperature air when both sides set to Lo.
I went to 2-3 small, local garages and without any inspection they said if one side cooling, the refrigerant is enough and compressor is working, problem is in driver side flaps.
Meanwhile I red some forums opinions saying similar problem been solved by adding some refrigerant in the system. This seemed to me no logical because evaporator is one for both sides and if refrigerant is insufficient, would suffer both sides...
Regardless of my logic I went to Halfords to check the system. The pressure gauge showed insufficient refrigerant. They added some (something like deodorant spray) and surprisingly (for me) AC started working. Side vents air dropped to 6-7 deg, middle ones to 4,5-6 deg. Now when AC is working, can hear noticeable rumbling around compressor area. (though I don't think this is so normal and not sure if gauge is correct and system is not overfilled)
In the view window on the pipe the stream again is turbulent, not smooth as some people say.
Self test showed almost the same values as before, I mean sensors 6 and 9 are C9 and b2 again and probably have a problem...

1 in-car temp .... 31
2 ambient ......... 26
3 solar light ....... 42
4 engine coolant 83
5 evaporator temp 7
6 drivers air mix % C9 (???)
7 passenger mix % 1
8 car speed ......... 00
9 vent temp air out b2 (???)
10 AC pressure 15 -- I don't know the units?

So £30 less in the pocket and AC is working, although I am not completely happy because of readings and compressor noise...

Just forgot to say- before and now I can control both sides heating. Before, when set by arrows both sides to "Hi", both sides blow warm air, when set to "Lo" just left side cooling. Now both sides settings Lo and Hi work

 

[freddofrog]

Just forgot to say- before and now I can control both sides heating. Before, when set by arrows both sides to "Hi", both sides blow warm air, when set to "Lo" just left side cooling. Now both sides settings Lo and Hi work

I've been away a while, and just read your post.

I'm not sure whether it's fixed ?

To be sure, forget the built-in "diagnostic" system, and what happens with the following

With engine fully up to temperature and with A/C ON .....

with DUAL OFF (driver's and passenger's sides operate together)
1. with temperature setting on Lo, do both sides blow very cold ?
2. with temperature setting on Hi, do both sides blow hot ?

with DUAL ON (driver's and passenger's sides operate individually)
3. with temperature setting Lo on passenger's side and temperature setting Hi on driver's side, does the passenger side blow very cold and driver's side blow hot ?
4. with temperature setting Hi on passenger's side and temperature setting Lo on driver's side, does the passenger side blow hot and driver's side blow very cold ?

 

[JapCar]

I've been away a while, and just read your post.

I'm not sure whether it's fixed ?

To be sure, forget the built-in "diagnostic" system, and what happens with the following

With engine fully up to temperature and with A/C ON .....

with DUAL OFF (driver's and passenger's sides operate together)
1. with temperature setting on Lo, do both sides blow very cold ?
2. with temperature setting on Hi, do both sides blow hot ?

with DUAL ON (driver's and passenger's sides operate individually)
3. with temperature setting Lo on passenger's side and temperature setting Hi on driver's side, does the passenger side blow very cold and driver's side blow hot ?
4. with temperature setting Hi on passenger's side and temperature setting Lo on driver's side, does the passenger side blow hot and driver's side blow very cold ?

I will report after test 1-4. When I tested I didn't remember position of DUAL, but both sides were Lo or Hi at the same time...