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2018 EX-L with the 1.5l, we live in a cold climate

My wife mostly drives this vehicle - Now into the second winter and was thinking about the long warm-up time we have experienced with this vehicle. Started thinking about the active grill shutters and what their role may be in this. After searching around the Internet the grill shutters should go through a start-up sequence when the motor is started...initially they should be open, should cycle close and open, then close. Mine did nothing...

I looked at the fuse(s) involved and there are two fuses controlling these shutters, one for the fog lights and lower grill and the other for the upper grill (and engage the system)...fuse #22 (FR FOG/LWR_SG) was fine as the fog lights work, fuse #23 (MG CLUTCH/UPR_SG) looked fine but I replaced it anyways...and the shutters now look to be operating as they should on vehicle start-up.

I didn’t tell my wife, and she notice much quicker warm up time the first time she drove it. So, if you are having heat up issues, this is an easy thing to check. According to information I have found, the purpose of these shutters seems to be aerodynamics...but seems to me that they would have a role in helping to control/maintain engine temps? Also, I changed the oil at the same time to see if the grill shutter operation some how affects the excessive oil fuel dilution issue I am having...maybe getting up to operating temps quicker???
 

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The shutters close when warming up to retain temps.
at startup i believe they cycle open and closed as a system check to make sure they arent obstructed or frozen
 

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The shutters close when warming up to retain temps.
at startup i believe they cycle open and closed as a system check to make sure they arent obstructed or frozen
If they do cycle open and closed as a "system check", why wouldn't an error code be thrown if his weren't working? What point is a system check, if there's nothing to check the system check?

Thanks Tjbouwhu, for posting your findings.
 

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If they do cycle open and closed as a "system check", why wouldn't an error code be thrown if his weren't working?
Probably because there are no switches or sensors to tell the system that the shutters are open or closed.
 

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If they do cycle open and closed as a "system check", why wouldn't an error code be thrown if his weren't working? What point is a system check, if there's nothing to check the system check?

Thanks Tjbouwhu, for posting your findings.
if your saying your fuse was bad. How could it check or error if it had no power.
(assuming the line runs down into a larger harness)
 

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I think there is a lot more to understand about those crazy shutters........as in their position when the vehicle is in gear AND moving.
 

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This could explain my long warm-up time this year vs. last winter! I have to check this out.
I have found that in cold weather that turning off the climate control system allows the engine to heat up 2 - 3 times as fast as when the system is on. My 2018 CR-V with the 1.5 L engine is the worst car for engine warmup that I have ever owned and I am talking about numerous cars from the 1930s through the present. I would think that Honda would have a fix for this problem and yes, slow warm up does contribute to the oil dilution problem.
 

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It doesn't help that with the "emission update" Honda did to my CRV last year, somehow the fan cranks to maximum every time I remote start the car and there is no way for you to turn it down either unless you push the Start button.
 

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..............somehow the fan cranks to maximum every time I remote start the car and there is no way for you to turn it down either unless you push the Start button.
When using "Manual Mode"......does the fan still crank to maximum when remote starting? (auto mode off)

I would suggest, when using remote start in cold weather, to not let the car sit idling (unless clearing glass). Get in, set the blower to "LO", set temp to "HI". Once engine RPM has dropped to 1200-1000.........drive. Driving heats up everything much faster than sitting idling.
 

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2018 EX-L with the 1.5l, we live in a cold climate

My wife mostly drives this vehicle - Now into the second winter and was thinking about the long warm-up time we have experienced with this vehicle. Started thinking about the active grill shutters and what their role may be in this. After searching around the Internet the grill shutters should go through a start-up sequence when the motor is started...initially they should be open, should cycle close and open, then close. Mine did nothing...

I looked at the fuse(s) involved and there are two fuses controlling these shutters, one for the fog lights and lower grill and the other for the upper grill (and engage the system)...fuse #22 (FR FOG/LWR_SG) was fine as the fog lights work, fuse #23 (MG CLUTCH/UPR_SG) looked fine but I replaced it anyways...and the shutters now look to be operating as they should on vehicle start-up.

I didn’t tell my wife, and she notice much quicker warm up time the first time she drove it. So, if you are having heat up issues, this is an easy thing to check. According to information I have found, the purpose of these shutters seems to be aerodynamics...but seems to me that they would have a role in helping to control/maintain engine temps? Also, I changed the oil at the same time to see if the grill shutter operation some how affects the excessive oil fuel dilution issue I am having...maybe getting up to operating temps quicker???
I just tried this on my 2018. Started it cold. Shutters closed and opened. Stayed open.
 

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I just got my 18 Ex back. 2 days at the dealer. Drove 30 freeway miles there from work. Temperature about 5 degrees. By the time service writer got to the car running outside engine temp was at 2 bars. In service bay tech said lower hose was ice cold. Service says after 2 days of diagnosis everything is working but they don't think it should be cold. Official Honda response told to dealer is that it's fine. Advice was to start the lemon law process
 

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I just tried this on my 2018. Started it cold. Shutters closed and opened. Stayed open.
For whatever it is worth the shutters will stay open IF the A/C compressor is on. Try pressing on Climate and turning the A/C to OFF. See if it helps at all.

I recall a poster here a year or so ago from NW Wyoming. His CR-V would maintain heat while climbing mountain passes but the temp gauge would drop to nothing after reaching the top and coasting for 5-10 minutes. His windshield would then fog up and he could not see. He ended up selling his car. I live in Houston and even here my 18 CR-V takes a while to warm up, much longer than my wife's 2010.
 

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There was a post few months back about replacing fuse 23 that caused the shutters to work even though fuse 23 looked ok. Active shutters are in general supposed to reduce warm up time in half (not sure about the ones on CRV). Also wondering if 1.5l engine is too small for warm up in reasonable time in cold weather. Why didn't Honda put an A/C button so users know the A/C is running in winter? The A/C also keeps shutters open (this logic I dont understand either). Shutter should be closed until engine reaches some temperature, A/C running or not.

sv11
 

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From Honda:

Active Shutter Grille System

Making its Honda debut on the 2017 CR-V, the new Active Shutter Grille system reduces aerodynamic drag at cruising speeds, directly helping to improve fuel efficiency on the highway. The system uses an electric step motor controlled by a processor that tracks major temperature parameters including engine coolant temperature, transmission oil temperature and air-conditioning requirements. The system either opens or closes the upper and lower shutters simultaneously to control the amount of air flowing through the engine's radiator and the air conditioner's condenser (plus the intercooler, for trims powered by the 1.5L turbo engine). The lower shutters leave a small area always open for optimum airflow even when the shutters are closed. The system is designed to keep the shutters closed as much as possible-even in city driving-for improved aerodynamic performance and fuel efficiency.


Honda says it's all about aerodynamics........I don't see anything about reducing engine warm-up time. City driving aerodynamics?.........come on Honda, really? My city driving is 30-35 mph.
 

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For whatever it is worth the shutters will stay open IF the A/C compressor is on. Try pressing on Climate and turning the A/C to OFF. See if it helps at all.

I recall a poster here a year or so ago from NW Wyoming. His CR-V would maintain heat while climbing mountain passes but the temp gauge would drop to nothing after reaching the top and coasting for 5-10 minutes. His windshield would then fog up and he could not see. He ended up selling his car. I live in Houston and even here my 18 CR-V takes a while to warm up, much longer than my wife's 2010.
At least with the original AC control module (don't have the flashed or new AC module upgrade), this helps a lot in warm-up time by keeping the AC (and Auto button) off, as noted.

I do something that some folks might not feel comfortable doing, but since I have a Scanguage that I can monitor CT1/2, when it starts getting consistently cold here (ave range in winter 40F to 20F), I mask-off the intercooler area grill area (leave the upper grills clear). It does seem to help in the warm up perioid, but does not noiciable increase in normal running the cabin temp, since the engine still stays in it normal operating range. When exteremly cold here, (-5F-10F), it also seems to help keeping the engine in typical operating rane of 175F+ easier at stoplights/etc.

The CRV is just not a hot heater as compared so my other cars in the past in the same area.
 

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I monitor with a ScanGauge as well.......when leaving the garage on a cold morning, it is interesting to see CT2 (cold radiator tank) drop while CT1 (engine coolant temp) increases.

While driving........wonder what position those crazy shutters are in??‍♂
 

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When using "Manual Mode"......does the fan still crank to maximum when remote starting? (auto mode off)

I would suggest, when using remote start in cold weather, to not let the car sit idling (unless clearing glass). Get in, set the blower to "LO", set temp to "HI". Once engine RPM has dropped to 1200-1000.........drive. Driving heats up everything much faster than sitting idling.
What's manual mode/auto mode with remote start and how do you turn it on/off?

I have to confess I don't read the user manual at all.
 
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