Honda defroster reprogramming
03-19-2009
#31
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Re: Honda defroster reprogramming
I guess this explains why I'm freezing my nuts off in my new 09 dx-g I bought last week .seems to take a long time to warm up even though blower is on full blast and heat is set to highest .
so let me get this straight
in a nutshell -the ac green indicator light doesnt come on even though the ac is on while the heater/cool function is on defrost or defrost/floor mode ?
my 99 did this as well but the ac green light would come one and I'd just switch it off
kind of annoying ?
I guess I'll try the work around
so let me get this straight
in a nutshell -the ac green indicator light doesnt come on even though the ac is on while the heater/cool function is on defrost or defrost/floor mode ?
my 99 did this as well but the ac green light would come one and I'd just switch it off
kind of annoying ?
I guess I'll try the work around
03-19-2009
#32
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I looked at the thread in closer detail and someone said that the canadian civics dont have this set up --so need not worry then ??
I'm canadian eh (new dx-g 09 last week)
finding that car doesnt warm up very fast compared to my 99 civic so I'm wondering if the a/c is on even tho nothing indicates it should be (like the green light)
this is messed up and very , very annoying --especially since many canadians have remote car starters --so what now ? --while car is warming up on a -30 morning I have to go and turn off the effing ac ?
my 99 would go to ac when set to defrost but at least the light would come on and you'd be able to disable it(turn off) before turning car off for the night --then , when using remote starter next morning you'd know car wasnt in ac mode
I'm very annoyed by this
p.s -my canadian civic manual says that it does go to auto ac when in defrost mode but to turn off ac just hit the button twice --once to turn on (even tho its already turned on , I guess its to turn on green light --wtf !) then hit it again to turn off
so either way I'm screwed on those cold mornings when I want to use remote starter as it'll have the ac on already
I'm canadian eh (new dx-g 09 last week)
finding that car doesnt warm up very fast compared to my 99 civic so I'm wondering if the a/c is on even tho nothing indicates it should be (like the green light)
this is messed up and very , very annoying --especially since many canadians have remote car starters --so what now ? --while car is warming up on a -30 morning I have to go and turn off the effing ac ?
my 99 would go to ac when set to defrost but at least the light would come on and you'd be able to disable it(turn off) before turning car off for the night --then , when using remote starter next morning you'd know car wasnt in ac mode
I'm very annoyed by this
p.s -my canadian civic manual says that it does go to auto ac when in defrost mode but to turn off ac just hit the button twice --once to turn on (even tho its already turned on , I guess its to turn on green light --wtf !) then hit it again to turn off
so either way I'm screwed on those cold mornings when I want to use remote starter as it'll have the ac on already
03-19-2009
#33
Re: Honda defroster reprogramming
If the green A/C light is not lit (when in defrost or floor & defrost) then IMO the compressor is not engaged. You should easily be able to tell (underhood fans noise, reduced power, clutch cycling on/off)
It is mentioned that if you move the selector from somewhere to one of those 2 settings the compressor (and the green A/C light) will come back on and you will have to release it again, but if you have it in one of those 2 settings and turn the car off and then re-start it the compressor will stay released.
It is mentioned that if you move the selector from somewhere to one of those 2 settings the compressor (and the green A/C light) will come back on and you will have to release it again, but if you have it in one of those 2 settings and turn the car off and then re-start it the compressor will stay released.
03-19-2009
#34
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yes , but craig -others here are saying the green light doesnt illuminate when in defrost mode or defrost/floor mode in their particular model -u.s ? canadian ?
some of the u.s is just as cold as canada so it doesnt make sense that they'd void the canadian models of this stupid method
I'm still new to the 09 and cant tell if the ac is engaged or not --my only symptom is that I'm not impressed with how slowly it takes to warm up the inside of the car compared to my 99 --and its only been -15 , not -35
I'm also finding (different topic) that the engine fan was goin on alot when idling at a stop light or when warmin up the car for 3 mins to head out --it was only around 10 celcius outside
some of the u.s is just as cold as canada so it doesnt make sense that they'd void the canadian models of this stupid method
I'm still new to the 09 and cant tell if the ac is engaged or not --my only symptom is that I'm not impressed with how slowly it takes to warm up the inside of the car compared to my 99 --and its only been -15 , not -35
I'm also finding (different topic) that the engine fan was goin on alot when idling at a stop light or when warmin up the car for 3 mins to head out --it was only around 10 celcius outside
Last edited by butch33; 03-19-2009 at 02:17 PM.
03-19-2009
#35
Re: Honda defroster reprogramming
If your fans are running that quick I would say your compressor is engaging. If it gets about +15 F here my temp gauge stays low for quite a while. But I have heat once the needle gets above the lowest mark. My fans would never cycle at that temp without it being used.
03-19-2009
#36
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thanks for the help craig
I need some canadian 8th gen owner feedback .I'm confused as to whether or not the dxg's sold in canada would have this feature / or not (mainly because of a comment made in this thread)
however , in reading my dxg manual -it states that the a/c comes on when defrost/or defrost /foot setting is chosen and the green indicator light doesnt come on
this doesnt make any sense to me one bit cause I practically use the defrost or defrost/foot setting year round --so technically --my a/c would be on for every waking moment of my new cars life --wtf man
I need some canadian 8th gen owner feedback .I'm confused as to whether or not the dxg's sold in canada would have this feature / or not (mainly because of a comment made in this thread)
however , in reading my dxg manual -it states that the a/c comes on when defrost/or defrost /foot setting is chosen and the green indicator light doesnt come on
this doesnt make any sense to me one bit cause I practically use the defrost or defrost/foot setting year round --so technically --my a/c would be on for every waking moment of my new cars life --wtf man
03-19-2009
#37
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Re: Honda defroster reprogramming
i dont understand most of whats being posted, but let me throw in that having the "a/c" on has nothing to do with how hot the heater gets. if you have the dial turned to hot, it should blow hot air with or without the ac being turned on. now if youre in freezing climates, then yeah the engine will take a long time to warm up. ive been in situations where even after 30 mins of driving, the temp was still below normal until i started to drive in a lower gear to keep the rpms up. so it may be that your car is just not warmed up enough for the coolant to heat the air. as a rule you should always leave the fan on at least one click in cold climate warmups, so the coolant in the heater core gets circulated with everything else. otherwise turning the heat on once the car has warmed up will introduce freezing coolant to a hot engine and possibly cause damage.
03-20-2009
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I did the trick and the recirculation light flashed / ac light came on --so the 'work around' seems to have worked for my canadian dx-g -09
11-07-2009
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You may have noticed that when you turn on the windshield defroster, by default, the a/c will run to provide de-humidified air to the windshield. That is the way Honda has set it up in most of its' recent models. To me, the annoying aspect is that in the defrost modes the a/c control is disabled and there is no way to turn off the a/c. In many situations (particularly warm, rainy conditions) it makes sense to have the a/c go on, but in others, like very cold damp weather, or when driving in heavy or blowing snow, when you are trying to minimize icing on the winshield, it doesn't seem to make sense at all. Also, the manual emphasizes how running the A/C decreases MPG and encourages owners NOT to run it whenever it can be avoided!
Fortunately, there is a solution to this problem that is not documented in the owners manual! As I said, it appears to work with most recent Honda models and I have tried it successfully on my 2006 Civic. Here's how to reprogram the defoster:
- With the key in the "Off" position, set the controls as follows.
- Blower control to "Off"
- Temperature control to coldest
- Mode button to select panel vents only (cannot be selected with the key off, so select this before turning the engine off before starting programming)
- Holding down the recirculate button AND the A/C button, START THE ENGINE. (Continue holding the two buttons) The recirculate button indicator light will flash for about seven seconds. Then the A/C green indicator light will flash on. The defroster is now reprogrammed!
Now the defroster will work as follows.
When selecting Defrost or Defrost + Floor the A/C will still come on, BUT so will the A/C indicator light, and the A/C button is NOT disabled. Now you can push the A/C button and turn the A/C off! It will NOT come on again if you stop the engine and then restart, although you can push the A/C button to turn it on if you wish.
Since in very cold weather I tend to leave the control in the defrost + floor with the A/C off, this works fine for me. Just remember to occasionally run the A/C for a while to keep the seals lubricated. (Just not all winter long!)
Fortunately, there is a solution to this problem that is not documented in the owners manual! As I said, it appears to work with most recent Honda models and I have tried it successfully on my 2006 Civic. Here's how to reprogram the defoster:
- With the key in the "Off" position, set the controls as follows.
- Blower control to "Off"
- Temperature control to coldest
- Mode button to select panel vents only (cannot be selected with the key off, so select this before turning the engine off before starting programming)
- Holding down the recirculate button AND the A/C button, START THE ENGINE. (Continue holding the two buttons) The recirculate button indicator light will flash for about seven seconds. Then the A/C green indicator light will flash on. The defroster is now reprogrammed!
Now the defroster will work as follows.
When selecting Defrost or Defrost + Floor the A/C will still come on, BUT so will the A/C indicator light, and the A/C button is NOT disabled. Now you can push the A/C button and turn the A/C off! It will NOT come on again if you stop the engine and then restart, although you can push the A/C button to turn it on if you wish.
Since in very cold weather I tend to leave the control in the defrost + floor with the A/C off, this works fine for me. Just remember to occasionally run the A/C for a while to keep the seals lubricated. (Just not all winter long!)
I just did my 09 Canadian Si. WORKS GGGGGREAT!
06-17-2010
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I have a new Honda Civic 2010 Ex and it has only 300+ mileage. Today morning I tried to strat my car but it seems that the steering wheel is locked. The key doesn't turn to ignite. Does anyone know how to fix this problem???
09-09-2010
#44
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Can anyone confirm if this works on the 2010 models? I'm probably going to get back into a Civic sedan this month (Canadian 'Sport' (LX) model). My current 08 CRV will not let you reprogram the A/C unlike my previous 05 CRV and 03 Civic.
09-09-2010
#45
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if it works with 2009 models, i dont see why not. its still the same 8th generation.
11-29-2010
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This is a good read. Strange though, I bought my 09 Civic Si last November, and noticed that when turning the defroster on, that the A/C button would come on, but I was able to turn it off. Never had to do this procedure, but good to know 
02-09-2011
#47
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I have a Canadian '09 Civic DX-G and in the defroster mode or in the "fresh air" (any mode with the foot vents activated) mode the AC light does not illuminate.
The manual says that if you are in either of the above modes the AC will come on in order to help defrost the window and keep it defrosted. The AC remains on when you switch to floor vents because you still have a tiny amount of air coming through the defrosters regardless of the vent position indicator switches position and the cooler air will help to maintain defrosted windows for a longer (albeit still short) time.
You can shut off the AC by pressing the AC button twice.
The manual says that if you are in either of the above modes the AC will come on in order to help defrost the window and keep it defrosted. The AC remains on when you switch to floor vents because you still have a tiny amount of air coming through the defrosters regardless of the vent position indicator switches position and the cooler air will help to maintain defrosted windows for a longer (albeit still short) time.
You can shut off the AC by pressing the AC button twice.
06-19-2011
#48
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i dont understand most of whats being posted, but let me throw in that having the "a/c" on has nothing to do with how hot the heater gets. if you have the dial turned to hot, it should blow hot air with or without the ac being turned on. now if youre in freezing climates, then yeah the engine will take a long time to warm up. ive been in situations where even after 30 mins of driving, the temp was still below normal until i started to drive in a lower gear to keep the rpms up. so it may be that your car is just not warmed up enough for the coolant to heat the air. as a rule you should always leave the fan on at least one click in cold climate warmups, so the coolant in the heater core gets circulated with everything else. otherwise turning the heat on once the car has warmed up will introduce freezing coolant to a hot engine and possibly cause damage.
Forgive the resurrection of an old post, but I am a newbie to the wonderful world of Honda Civics.
If I understand you correctly, you are saying that engine coolant does NOT circulate thru the heater core when the cabin fan switch is off? This says that there must be either a separate coolant pump for the heater or a valve that only allows coolant to circulate when the cabin fan is operating. Is this correct? My 2011 Civic LX Coupe has warm air (small amount) circulating from the vents when the vehicle is moving and the cabin temperature control is set on heat. Granted there is not a lot of air flow, but it is there nonetheless. The temperature of this air flow will change with the temperature setting called for. Clarification please?
Also, thanks to the original poster for the reprogramming information provided. I will try it later tonight or tomorrow.
06-20-2011
#49
Re: Honda defroster reprogramming
There is a valve that controls the amount of coolant flow through heater core for heating. The blue/red **** controls this.
It is normal to get a small amount of air flowing through the system when fan is off.
It is normal to get a small amount of air flowing through the system when fan is off.
06-20-2011
#50
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So what you are saying is that the FAN being on/off has nothing to do with the coolant flow, and that the temperature control actuates a valve that controls the coolant flow thru the heater core. Is this correct? If so, it fits the condition that I was describing with the temperature controllable air flow thru the vents when the car is moving and the fan is off. Thanks for the reply.
Last edited by Crusty; 06-20-2011 at 09:46 AM.
06-20-2011
#52
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Re: Honda defroster reprogramming ^That's what I thought. I am in process of trying to get the complete set of wiring diagrams for the 2011 Civic Coupe without breaking the bank. No luck so far.
On the subject of this thread, I did the reprogramming of the A/C defrost mode on my 2011 LX Coupe. Worked like a charm. Now all I have to do is remember to turn on the A/C compressor occasionally during the winter. Thanks for the great info.
On the subject of this thread, I did the reprogramming of the A/C defrost mode on my 2011 LX Coupe. Worked like a charm. Now all I have to do is remember to turn on the A/C compressor occasionally during the winter. Thanks for the great info.
06-20-2011
#53
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some air blows thru the vents because the air intake is in front of the car (under the wipers) and air will move in when the car is in motion, even if the fan is off. if you do not want any air blowing in (not recommended), you can press the "recirc" button so that it closes the system to the outside air. thats an easy way to kill yourself tho...
06-20-2011
#54
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some air blows thru the vents because the air intake is in front of the car (under the wipers) and air will move in when the car is in motion, even if the fan is off. if you do not want any air blowing in (not recommended), you can press the "recirc" button so that it closes the system to the outside air. thats an easy way to kill yourself tho...
No, that's not where we were going with this. We(I) was trying to understand how the temperature control function works on the Civic. Most vehicles I have owned in the past used a hot/cold air mix plenum to achieve temperature control. It seems the Civic is of a different ilk. I understand why I have air circulation thru the vents when the car is moving. It was just the temp control situation I was going after. No problems, just clarification.
Last edited by Crusty; 06-20-2011 at 08:10 PM.
06-20-2011
#55
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oh okay. yeah you can look under the hood for the valve if you want and have someone turn the temp dial. you will see the valve close and open. its towards the back of the bay where the smaller heater hoses are going into the dash. spraying some silicone on it is a good idea to keep it from binding. they have a tendency to rust up over time.
12-03-2011
#56
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Re: Honda defroster reprogramming
Tried this programming trick on my new 12 Civic, worked like a charm. Didn't have to start the engine.
I know there are self-diagnosis modes that are accessed with a "button dance" but this particular trick is not documented in the service manual.
I know there are self-diagnosis modes that are accessed with a "button dance" but this particular trick is not documented in the service manual.
01-26-2012
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11-14-2017
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If you think a good mechanic is expensive, try hiring a bad one
02-07-2018
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I have done the reprogramming and it works. But I hate having to turn the A/c off every time i hit the defrost function during the winter. Is there a way to pull the fuse (Fuse #20 = MG clutch) or relay connected with the a/c compression to fully stop it from functioning at least for the few months in the winter time????
Relay with single snowflake was pulled but compressor still turns on.
Please help
Relay with single snowflake was pulled but compressor still turns on.
Please help
