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Discussion Starter #1
I have seen a couple of videos on the 2017 that show the electronic louvers that close when the car is at high speed and low temps to block the radiator in order to reduce drag at high speeds, but I have not seen any mention of it on the 2018.

I personally kind of thought this might be a bad idea and that theory was only reinforced when I read in the manual that if the engine is starting to overheat you should check the louvers to see if they are stuck closed. I know the 2018 CR-V's they sell for warmer climates do not have the Louvers for obvious reasons but I wondered if it has been removed from all the models?


Rob
 

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From my understanding, Honda didn't make any mechanical changes to the 2018 CR-V. Honda's website also lists the Active shutter Grille for all 2018 USDM CR-V trims. It would be pretty odd for Honda to just remove the feature seeing as it does aid in the vehicle achieving its 32+ MPG on the highway.
 

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Agree. Due to the complexity of this vechicle, I felt justified in getting the HondaCare warranty. For 8 years/120k miles, most repairs and towing are gong straight to a Honda dealer. Just peace of mind and Ido like the CR-V- complexity and all.
 

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I do find my CR-V takes awhile to warm up on a cold morning.Many miles before the temp gauge starts rising.A scary long time.Makes me wonder of the shutters are working properly.
 

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I do find my CR-V takes awhile to warm up on a cold morning.Many miles before the temp gauge starts rising.A scary long time.Makes me wonder of the shutters are working properly.
Sounds more like the thermostat is stuck in the open position.
 

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I do find my CR-V takes awhile to warm up on a cold morning.Many miles before the temp gauge starts rising.A scary long time.Makes me wonder of the shutters are working properly.
In 20 degree weather it takes about 6 miles before max temp happens...but heated seats and auto climate seems to work OK during this time.
 

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In 20 degree weather it takes about 6 miles before max temp happens...but heated seats and auto climate seems to work OK during this time.
20's temps.About 6 miles or another mile or two.Just seemed kind of long.That was with a minute warm up.
You're right on the heated seats.I don't remember about the climate control.
I would think such a small engine would get to normal temp quickly.
 

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Discussion Starter #10 (Edited)
The crvs for warmer climates do have active shutters. They start out open and are moved to open on shutdown. They are cycled at startup as a test and use reliable stepping motors. Plus there is still a part of the lower grille that is open all the time. I would suggest if complexity in a car is a concern, the crv is not for you. http://www.crvownersclub.com/forums/137-2017-present-official-specs-features-etc-gen-5/153369-active-shutter-grill-feauture.html
LOL first of all I am a full time EE and design some of those "Modern Circuits Boards" that are used in products. I have no problems with something being modern, but at the same time I also realize that in recent years many "Modern Designs" tend to be gimmicks that offer little benefit and mostly add a huge increase in product failures. Just look at any of the newer refrigerators or washing machines and you will understand.

When you say you see CR-V's for warmer climates with Louvers please tell me which ones. I have looked at the RV, the RVSI, the VTI-l, VTI-s and I see no mention of louvers. I have personally looked at the RV and RVSi and they do not have louvers.
I cannot see how you can possibly block the radiator in 92 Deg temperatures without quickly overheating the engine. So I can understand why they would not include them.

Your assessment that stepper motors are very reliable, is not the issue, the problem is that all electric motors and moving louvers are magnets for possible problems. All it takes is some low lying bush branches to get in through the vent and jam the louvers closed or even mud or ice/snow can jam up the works.

The meager figures used of 2-3% increase in efficiency, which is based on truck statistics hardly sounds like it will hold up on a CRV-V that has a radiator area 1/10 the size of an 18 wheeler, so we are probably looking at 1% or less gain in fuel efficiency. Even that I am skeptical of. I remember years ago we did some test on Ku Band antennas with 2mm wide holes in the mesh and at high wind speeds like 60 MPH they almost acted like solid panels. Kind of makes me wonder how much of a change a louver will even make. Maybe that's why they dumped this tech in cars after the 1940's.

Rob
 

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I do find my CR-V takes awhile to warm up on a cold morning.Many miles before the temp gauge starts rising.A scary long time.Makes me wonder of the shutters are working properly.
It's definitely cold blooded. I need to drive a good few minutes before any real heat from the fan comes my way.
 

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The warm up time of your vehicle has a lot to do with how you drive it. Its obvious that the heat comes as a by-product of the fuel burned in the engine. The more fuel you burn the more heat you make. The manufacturer knows very well how long it takes to heat up and there is even an OBD II trouble code for excessive time to warm up. In the criterial for setting that code the ECM actually considers the load factor that has been placed on the engine. The example I used in class was that there were two identical cars. Driver number one lives on top of a mountain and in the morning he would pull out his drive and then proceed to travel down the mountain. He would likely have the throttle closed (which cuts fuel off) and his car would not warm up very quickly at all due to lack of engine heat being produced. Driver number two lives down in a valley and when he leaves for work he has to drive up that same mountain to get to his job on top of it. He has to push hard on the gas to make enough power to go up that steep grade. Guess what...he burns a LOT of fuel and his engine warms up quickly.
In OBD II we have a trouble code P-0125 which tracks the time it takes an engine to get warm enough to go into closed loop. Some vehicles have a code that will set if the car takes too long to get to normal operating temperature. Both are based on testing that verifies how long a normal engine in proper operational condition and being driven under "normal" conditions (not the extreme with the mountain!) would take to warm up. There is a "counter" that moves forward with increased load and counts backwards when the vehicle goes into coast mode as it will actually cool off under coast.

On my '17 CR-V (and my 2015 Fit) the engines warm up at the fist stop I make leaving my home. That stop is less than a mile away. I can't say the engine is at full operational temperature yet but the heater is certainly blowing out some hot air in the first mile.

The cooling system on many modern vehicles is piped so that the heater core can get the warmest coolant first. In fact when its very cold outside and under certain slow speed driving modes or down hill coasts the heater core can sometimes actually remove more heat from the engine than the radiator does. Think about it....

As for all this "electronic complexity", you worry all you want, I don't lose any sleep over it. Years of work in the field showed me that electronics were pretty darn reliable overall. As we went to more and more computers in cars we actually saw a reduction in warranty costs on electrical systems. What I really like is that when something does go amiss I could use a scan tool to zero right in on the problems saving a lot of tedious (and expensive) diagnostic time.

As for the shutters, I could see them more for temperature regulation and helping the air conditioning evaporator to work better. On many vehicles the engine controller monitors outside air temperature and controls electric fan speeds to keep both the radiator and evaporator at the ideal temperatures. As any high school science student knows heat exchange works best when there is a greater temperature between the two objects. Rather than have multiple cooling fans with lots of relays and wiring they have chosen to use the shutters to control the air flow. Of course this air flow going through these parts does have turbulent that causes drag so there are a couple of reasons to use them. I know back in the 1990's when we first started doing these things we cut off all the fans after about 25 miles per hour as they actually did nothing to help cool the engine and were a source of drag. Some cars had passive shutters to that would change the air flow if the fan were on when the vehicle was at rest. There is a lot of physics going on with a vehicle in motion.
 

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Discussion Starter #13
As for the shutters, I could see them more for temperature regulation and helping the air conditioning evaporator to work better. On many vehicles the engine controller monitors outside air temperature and controls electric fan speeds to keep both the radiator and evaporator at the ideal temperatures. As any high school science student knows heat exchange works best when there is a greater temperature between the two objects.
Yes I would agree but the problem is in terms of cooling there is no situation where closing the Louvers/shutters is going to make the evaporator coil any cooler, unless there is some hidden air redirection happening behind the grill.

Rather than have multiple cooling fans with lots of relays and wiring they have chosen to use the shutters to control the air flow. Of course this air flow going through these parts does have turbulent that causes drag so there are a couple of reasons to use them. I know back in the 1990's when we first started doing these things we cut off all the fans after about 25 miles per hour as they actually did nothing to help cool the engine and were a source of drag. Some cars had passive shutters to that would change the air flow if the fan were on when the vehicle was at rest. There is a lot of physics going on with a vehicle in motion.
I also agree that there are small and I mean small benefits to speed and gas mileage by doing this but IMO it not enough to justify the very possible risk that several years down the road this piece of equipment may fail and make your engine overheat or in the worst case scenario get stuck half way closed and have your engine running hotter than it should be for months on end. I have seen a few cases of people having radiators in dire need of rodding out or being changed yet they continued with them until the excess heat finally caused other major problems. This could have the same effect!

My thinking on this is that Honda mainly put them there for a faster warm up of the engine and therefore the heating system when the car is started up during the winter. It fits in nicely with remote start, the heated seats and the heated steering wheel which are all designed to have your car toasty warm in 10 minutes.

Rob
 

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Went by the local Honda dealer today.....all the 2018 CR-Vs on the lot had AGS identical to the '17s. There is no area of the inter cooler/condenser/radiator that is not covered by the shutters. Best I can tell, if the a/c compressor is engaged, the shutters are open AND the efans are on. For faster engine warm-up, make sure the a/c is off so the shutters will close and the efans will be off.

According to my OBDII scanner, the system enters "closed loop" within seconds of a cold start due to heated O2 sensors heating up super fast. The motor can run clean/green way before coolant reaches operating temp.
 
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