[jayoldschool]

Figured I'd jump in since the no heat party is getting big!

2015, heat only works on hold mode. When the engine is running, the heat icon bottom right on the climate screen will activate. It will not activate when the car is EV. Not on Eco, Comfort or Auto, not at 30C or HI. Cold air from the vents. Last (first) winter, my wife ran it mostly on ECO, she was trying to maximize range, and it wasn't cold very often, so not actually sure if it worked properly then or not.

Is there something I'm missing to turn the heat on when it's operating on battery? I got in it and experimented with the controls when she got home from work, but I could not get that heat icon to illuminate, no matter what the selection. All selections produced cold air. This was in a heated garage, immediately after a 25km drive.

The climate power display does change accordingly with ECO/Comfort/Auto, but that heat icon will not illuminate.

I've got the owner's manual here, and I'm going through other threads to research. Planning to stop by the dealer tomorrow if I can't figure out where we're going wrong.

Thanks for the advice.

 

[voganni]

Hmm, heat/cool icons are bottom right on climate screen, heat is right one. It should not be on in hold, as you are using engine heat. Set your DIC to the power gauge, turn on the car, set the heat to Comfort and Hi. The heat icon should say "on" and you should see up to 6kw of power draw on the gauge with car stopped in park. And you should have heat in a minute or so. If you see a power draw but get no heat, I'd suspect the switching valve. No heat "on" icon and no power draw, I'd suspect the K-10 heater module. To fix either issue you're looking at a dealer visit. Complex system and the heater module runs on 300v supply from main battery.

 

[llninja]

My 2013 volt is set on comfort and 74 degrees and I always get heat. There were some times in the first few months of ownership where I would get no heat like you, but it was only once or twice a month. I took it into the dealership, the service note said "found doc #10281005. Reprogrammed the HVAC control module. No codes stored at this time"

I haven't had the no heat issue since.

A year ago, I decided to stop trying to eek out every mile. I just drive it and don't worry about the EVrange. it goes as far is it goes for the conditions. trying to squeeze out more is just too much work, and I don't' née any more stress and angst in my life oespecailly when you almost get to 50 miles of EV range and the ICE turns on right after my last turn into the driveway (happened ore than once). To rid myself of that frustration, I make sure to blow my EV range early and ensure I hit the Dino juice.

 

[saghost]

Sounds like a hardware problem. In Eco or Comfort the electric heat should come on automatically when the temperature calls for it. Time to see the dealer.

 

[WopOnTour]

It's actually sort of difficult to nail down a NO HEAT condition on a Gen1 Volt, as we've seen a lot of different failures.
Low coolant, bad electric pump, bad Coolant Heater Control Module (CHCM), bad flow control valve, bad heater core, even restrictions (in most cases a poorly documented coolant filter)

Then, that's all exasperated by the fact that GM hasn't really done a very good job in the owners manual when it comes to a "Poor/No heat" concern.

Over the course of the last couple of winters, I have taken the liberty to add "updated" information to the GM materials. I've shared it with a few Volt techs now and it has helped in getting to a root cause a little smoother. I've attached some of it below. Feel free to pass it along as it might help.

WOT

 

[driver779]

I recently had a serious squirrel nest building problem in my 2012 Chevrolet Volt, as they were coming into the HVAC system when I was parked at work. We have seriously bad-a$$ city squirrels in Minnesota. Despite being cleared out in October, I will find various things from time to time such as seeds or a few black walnuts.

I bring this up, because you should seriously consider looking around with a good decent flashlight and see if you have any blockage from rodent friends.

Try this test: Take everything off Auto. Manually increase the fan, put arrow on either upper or lower vent and put the desired temp to HI. Let it run, do you hear anything flying around in there at max speed?

 

[voganni]

Ugh! Pureed squirrel would be hell to get out of the blower!
Good information as usual WOT. However, how can one feel the heater core inlet hose with the hood closed? lol

 

[WopOnTour]

Ugh! Pureed squirrel would be hell to get out of the blower!
Good information as usual WOT. However, how can one feel the heater core inlet hose with the hood closed? lol

It's done under the dash
Alternatively you can temporarily "flip" the hood latch
It's just so ICE doesn't run
WOT

 

[viking79]

You are using the heater correctly.
Comfort and Eco basically mean "Electric heat on"
Fan only means blow air in, if you have the temp selector set to hot it will blow it across the heat exchanger and if the engine was running and warm, the air coming in will be warm. Fan only works like the fan on any ICE vehicle.

When you hit comfort it should turn on the electric heating element and that should heat coolant and start blowing warm air after a few minutes. Check climate usage on energy window, should be 50-100% range depending on temperature and such.

I would read through WopOnTour's post and see what might not be working, or take it into the dealer if you don't work on your own cars or if it still is under warranty (2015 should be under the general 3yr/36k mile warranty). Might be worth doing obvious, like checking fuses first.

Edit: I am not familiar with the heat icon. If set to comfort with engine cold (like first thing in the morning) and given 5 minutes or so, is the air coming out of the vents warm?

 

[jayoldschool]

I am comfortable with my own work, I've worked on cars for 25 years. However, this one's under warranty, so they get to fix it. I have brought home my new SnapOn scanner to go through the functions before the dealer gets it. Dropped by today, it will go in on Friday.

Viking, no heat. No matter how long you wait.

Double checked the DIC, when you select Comfort, draw increases 6kW. Eco, 4kW. So, looks like the heating element is working. That means the problem will be coolant related. Pump, valve. The level is good, checked yesterday. No leaks. Fan works fine, no critters in there. It has a cabin filter.

 

[bnseaside]

Make sure you have the Temp set at 23 or 24. If you have it turned down for the summer and then turn on your heater without turning up the temp. you will only get cold air no matter on comfort or eco. Sounds like you have it down to low and your air conditioner is running.

 

[jayoldschool]

As I pointed out in post #1, the heat doesn't work on 30° Celsius (86F), or the next one up, HI. The AC is not on, the heat is not too low.

 

[voganni]

You see a kw draw on the DIC but still no "on" indicator on the heat icon? Strange. Fairly easy to verify if the pump is running, should be able to hear/feel it near the right front wheel. You should probably feel some warm coolant in the hoses too. Looks like fuse #13 in under-hood fuse panel is for pump and valve. Check that.

 

[jayoldschool]

Yes, power draw when heat is called for, no heat icon, no actual heated air. Will check that fuse, thanks! Didn't have time to get the scanner on it today, will update tomorrow.

 

[jayoldschool]

Sorry about the long wait for updates, we dropped the car off and are on vacation. Problem diagnosed as the heater coolant pump. They are waiting for the part to arrive from the US.

 

[jayoldschool]

Pump came in on Thursday, we picked the car up on Friday. Heat works perfectly. It had never worked properly since new, but we were unaware as the mild winter last year allowed reasonable operation without E heat. When it was really cold, it was on ICE. There is a small audible hum/vibration when the pump is operating, which never happened before. It was under warranty.

 

[TheNathanielWatkins]

Yes, power draw when heat is called for, no heat icon, no actual heated air. Will check that fuse, thanks! Didn't have time to get the scanner on it today, will update tomorrow.

I'm having the same problems with my recently purchased 2014. When you checked fuse/relay #13, did you find one there? Mine is completely missing the relay in spot #13, and since I'm? new to this Volt, I'm not sure what was done to it before I got it. I've tried to get the relay from two dealerships in my area, but they've both told me that Volts aren't supposed to have a relay there, even though the owner's manual says otherwise. On a related note, the owner's manual said the relay in spot #3 was unused, but when I removed it I got a check engine light talking about the emissions system (went away after a couple of charge cycles with it back in place).

Can anyone else willing to help also check if you actually have a relay in spot #13 of the engine fuse block? If so, would you mind telling me the part number and/or specs listed on the relay? The parts people at both those dealerships both said they couldn't look up what relay should be there without reading the numbers of an existing one.

On another related note, can any Seattle-area Volt owners recommend a dealership service department? The one I bought mine from (Good Chev in Renton) and the one with the seemingly best reviews I found on Yelp (Bill Pierre in Lake City, Seattle) both didn't? inspire confidence in their competency, when talking to them.

Lastly, excuse my ignorance. What's a Volt Advisor (keep seeing people mention talking to them)? Is there someone I can talk to at GM directly assigned to helping Volt owners?

 

[Bugstrider]

Our 2015 Volt just started exhibiting the same symptoms.
https://youtu.be/TRu-uk22FXs
Lastly-
I got into the car, hit the power button and armed with the camera, took the following sequential pictures.

After I hit the “ON” button

Start-up

—————
Climate set to auto

—————
Initial KW ramp-up draw

Climate control temp set to “HI”

—————
The KW drop-off

AC icon would switch to Off/On/Off over the course of a few minutes. Only cold air would be pushed through the vents.

Thanks



Sent from my iPhone using Tapatalk

Sent from my iPhone using Tapatalk

 

[Jim_N_Tonic]

Our 2015 Volt just started exhibiting the same symptoms.
https://youtu.be/TRu-uk22FXs
Lastly-
I got into the car, hit the power button and armed with the camera, took the following sequential pictures.

After I hit the “ON” button

Start-up
—————
Climate set to auto
—————
Initial KW ramp-up draw
Climate control temp set to “HI”
—————
The KW drop-off
AC icon would switch to Off/On/Off over the course of a few minutes. Only cold air would be pushed through the vents.

Thanks

Looks like mine has started doing the exact same thing as Bugstrider's car. With the (hopefully last) onset of cold weather these last few days I tried to use heat in EV mode to no avail... Car heating works as normal with the engine running. My commute is about 76 miles each way, so I drive on the ICE on the way to work, and then use the EV mode for the last half of the drive home. Both yesterday and today I had no heat available in EV mode, but running the ICE creates a blissful amount of warm air.

I'll have to check the fuses and the coolant level when I leave work today to see if there's something amiss with either of those items.
If not, I'll be researching the 3 way valve and the coolant pump as a possible problem...

At least I made it 6 months and 21,000 miles with no issues....

 

[turboguy327]

Our 2015 Volt just started exhibiting the same symptoms.
https://youtu.be/TRu-uk22FXs
Lastly-
I got into the car, hit the power button and armed with the camera, took the following sequential pictures.

After I hit the “ON” button

Start-up

—————
Climate set to auto

—————
Initial KW ramp-up draw

Climate control temp set to “HI”

—————
The KW drop-off

AC icon would switch to Off/On/Off over the course of a few minutes. Only cold air would be pushed through the vents.

Thanks



Sent from my iPhone using Tapatalk

Sent from my iPhone using Tapatalk

This is a coolant pump problem. Super easy and cheap to DIY.