Cabin Heat & Defroster in EV mode

[davidnyc06]

I experienced this problem a few days ago and wonder if anyone has had a similar experience. This occurred while I was driving through freezing rain, which was freezing on my windshield.

 

When I started the car the ICE was running and heated the cabin and windshield so nothing froze on the windshield. However, after the engine was warm, the car would run in EV mode while I drove through some downhill stretches at about 30mph. During that time the HVAC just blew cold air while in EV mode, so the rain started freezing on my windshield. The ICE wasn't kicking in because the thermostat showed the engine as being warm and I wasn't drawing much battery power. I had to slow down and tap the accelerator every so often to get the ICE running and some heat. I'm sure the driver behind me was wondering what I was doing.

 

I had the cabin temp set to 75 and tried it in both EATC and front window defrost. I tried upping it to 85 and got only cold air in EV mode.

 

This worries me because I was thinking if I or someone else was stuck in snow overnight, the car wouldn't be able to generate consistent heat. The ICE wouldn't turn on unless the engine temp falls or battery power is drained so the car would have to get somewhat cold before the ICE would run and the HVAC could generate heat.

 

Has anyone else experiences this problem or is there a defect with my vehicle? Since there is no way to manually keep the car in ICE mode, I assume there is no way to ensure consistent HVAC cabin heat?

[Jaradel]

I experienced this problem a few days ago and wonder if anyone has had a similar experience. This occurred while I was driving through freezing rain, which was freezing on my windshield.

 

When I started the car the ICE was running and heated the cabin and windshield so nothing froze on the windshield. However, after the engine was warm, the car would run in EV mode while I drove through some downhill stretches at about 30mph. During that time the HVAC just blew cold air while in EV mode, so the rain started freezing on my windshield. The ICE wasn't kicking in because the thermostat showed the engine as being warm and I wasn't drawing much battery power. I had to slow down and tap the accelerator every so often to get the ICE running and some heat. I'm sure the driver behind me was wondering what I was doing.

 

I had the cabin temp set to 75 and tried it in both EATC and front window defrost. I tried upping it to 85 and got only cold air in EV mode.

 

This worries me because I was thinking if I or someone else was stuck in snow overnight, the car wouldn't be able to generate consistent heat. The ICE wouldn't turn on unless the engine temp falls or battery power is drained so the car would have to get somewhat cold before the ICE would run and the HVAC could generate heat.

 

Has anyone else experiences this problem or is there a defect with my vehicle? Since there is no way to manually keep the car in ICE mode, I assume there is no way to ensure consistent HVAC cabin heat?

 

That sounds like a defect to me. I was in EV mode for most of my commute home because I was driving so slow, and I never noticed the HVAC blowing cold air. I also rarely set my cabin temp above 70, and have been quite comfortable.

 

I have also been in situations where I was idling for long periods, and the ICE kicks in periodically - it doesn't stay on EV the whole time, or even for extended stretches.

[rfruth]

I don't drive thru freezing rain but when you kicked it up to 85 the ICE should have come on and supplied the required heat, the thermostat or the CTS (coolant temp sensor) could be malfunctioning (ie screwed up)

[eneg]

I experienced this problem a few days ago and wonder if anyone has had a similar experience. This occurred while I was driving through freezing rain, which was freezing on my windshield.

 

When I started the car the ICE was running and heated the cabin and windshield so nothing froze on the windshield. However, after the engine was warm, the car would run in EV mode while I drove through some downhill stretches at about 30mph. During that time the HVAC just blew cold air while in EV mode, so the rain started freezing on my windshield. The ICE wasn't kicking in because the thermostat showed the engine as being warm and I wasn't drawing much battery power. I had to slow down and tap the accelerator every so often to get the ICE running and some heat. I'm sure the driver behind me was wondering what I was doing.

 

I had the cabin temp set to 75 and tried it in both EATC and front window defrost. I tried upping it to 85 and got only cold air in EV mode.

 

This worries me because I was thinking if I or someone else was stuck in snow overnight, the car wouldn't be able to generate consistent heat. The ICE wouldn't turn on unless the engine temp falls or battery power is drained so the car would have to get somewhat cold before the ICE would run and the HVAC could generate heat.

 

Has anyone else experiences this problem or is there a defect with my vehicle? Since there is no way to manually keep the car in ICE mode, I assume there is no way to ensure consistent HVAC cabin heat?

I don't think that you have a problem, I think that you were just a victim of circumstances.

Of course, I can't say for sure, but I can tell you that if you ever have the misfortune of being stuck in the snow, or whatever, just put the transmission in either Park

or Neutral and just hold your foot on the accelerator. The ICE will come on and you should get all of the heat that you would need. . .

 

Eneg

[lolder]

I think you have a problem. Heating calls for the ICE to run until it gets to about the "C" on the gauge. After that, heating and defrosting should be continuous without attention. Normal vehicle movement will satisfy the heating demands as the ICE runs intermittently. If the ICE doesn't run enough, the heating demands will start it.

[davidnyc06]

I think you have a problem. Heating calls for the ICE to run until it gets to about the "C" on the gauge. After that, heating and defrosting should be continuous without attention. Normal vehicle movement will satisfy the heating demands as the ICE runs intermittently. If the ICE doesn't run enough, the heating demands will start it.

 

To clarify the situation, the thermostat was way above "C" on the gauge, near the middle. The ICE did run intermittently throughout.

 

However, when the ICE would shut off in EV mode, the HVAC would blow cold air. The HVAC heating demand didn't cause the ICE to run, and no ICE meant no heat.

 

This was a problem in my situation because the freezing rain would immediately build up on the windshield without constant heat.

 

 

The interesting thing I realized this month is that when I start the car on a cold morning and the temp gauge is below "C", the EATC keeps the HVAC blower at low speed until the car warms up. So everything seems to be working correctly; ICE runs when the thermostat is below "C" and the EATC has generally kept the car at the cabin temp I want.

 

It's just that cabin heat demand doesn't cause the ICE to run.

[lolder]

When the ICE shut off, the HVAC should not have blown cold air.

[MrMikeL]

Have you checked your coolant level?

[lolder]

You may have a bubble in you cooling system that may need "bleeding". See other thread "FFH Heater Failure".

[Myron Graessle]

Driving on the freeway a week or so ago through "wintry conditions", the snow changed to wet sleet. It gradually started building up on my windshield, until I realized it was getting very difficult to see. I switched the climate from the automatic 70 degrees to just the windshield defrost with the fan. One I did this, the ice melted and the windshield was clear again.

 

I'm guessing that the automatic mode doesn't push much air, warm or otherwise, to the windshield vents.

[davidnyc06]

I don't think that you have a problem, I think that you were just a victim of circumstances.

Of course, I can't say for sure, but I can tell you that if you ever have the misfortune of being stuck in the snow, or whatever, just put the transmission in either Park

or Neutral and just hold your foot on the accelerator. The ICE will come on and you should get all of the heat that you would need. . .

 

Eneg

 

I was reading the manual and learned that you can't engage the ICE in Neutral. I tested this and found it to be true. However, you can put the transmission in Park and hold the accelerator to make the ICE run.

 

Unlike the heater failure thread, my HVAC does generate heat, just not consistently in EV mode. If anyone wants to test this on a cold day, just turn up your cabin temp. I can feel a clear difference in HVAC air temp between when the ICE is running and when the car is in EV mode. I've also seen no problem with the coolant level.

[lolder]

I was reading the manual and learned that you can't engage the ICE in Neutral. I tested this and found it to be true. However, you can put the transmission in Park and hold the accelerator to make the ICE run.

 

Unlike the heater failure thread, my HVAC does generate heat, just not consistently in EV mode. If anyone wants to test this on a cold day, just turn up your cabin temp. I can feel a clear difference in HVAC air temp between when the ICE is running and when the car is in EV mode. I've also seen no problem with the coolant level.

If your ICE is warm as shown by being in the middle of the temperature gauge, you should see very little difference in the HVAC heat output in EV mode.

[eneg]

I was reading the manual and learned that you can't engage the ICE in Neutral. I tested this and found it to be true. However, you can put the transmission in Park and hold the accelerator to make the ICE run.

 

Unlike the heater failure thread, my HVAC does generate heat, just not consistently in EV mode. If anyone wants to test this on a cold day, just turn up your cabin temp. I can feel a clear difference in HVAC air temp between when the ICE is running and when the car is in EV mode. I've also seen no problem with the coolant level.

Hi,

 

I wish that I could help you more with this, but right now it's pretty warm in Florida.

As soon as it cools down a bit, I will try this as I'd like to know this for myself.

 

I'm a little confused though. In your original note you had said that the air was "cold" in EV mode.

Was it really cold, or just not as hot while in EV?

 

I've driven "normal" cars that couldn't keep the windshied free of ice if the conditions were really bad. Had to use the winshield washer to help out.

If in fact while driving in EV mode that the temperature does cool off by a couple of degrees, that just might have made the difference for you that night.

 

What really has me baffled though is that my car doesn't stay in EV for very long (at least the way that I drive it.)

So, even if the heated air was to cool down a little, I'd probably never notice it as the ICE is on most of the time.

 

I would still GUESS that you don't have a problem with this.

 

There should be plenty of FFH'rs who could try this out for you in colder climates.

 

Please keep us updated on this. . .

 

Eneg

[Dyoct]

There's an auxillary coolant pump that is electric to keep heat going when in EV mode. I had a customer's hybrid that wasn't getting power on the circuit that powers that pump. If you have the engine up to temp and you have the heat on and go to idle, once the gas engine shuts off, does it blow cool air?

[rfruth]

so does the auxiliary coolant pump keep coolant flowing in summertime when in EV mode it must ?

[lolder]

I'll bet the electric pump is bad or inop.

[davidnyc06]

There's an auxillary coolant pump that is electric to keep heat going when in EV mode. I had a customer's hybrid that wasn't getting power on the circuit that powers that pump. If you have the engine up to temp and you have the heat on and go to idle, once the gas engine shuts off, does it blow cool air?

 

 

You have described exactly what is happening with my car. I knew I was likely to get an answer on this forum. I guess I'm going to have to find some time to take the car to the dealer to get it fixed.

[davidnyc06]

Is it the same pump mentioned in the following link?

 

http://www.fordfusionforum.com/index.php?/topic/4194-electronic-coolant-pump/

[lolder]

Is it the same pump mentioned in the following link?

 

http://www.fordfusionforum.com/index.php?/topic/4194-electronic-coolant-pump/

I don't think so. If that pump were inop a lot of warnings would pop up.

[davidnyc06]

After some internet research, I've found:

 

Part 8C419 is the Motor Electronics Cooling Pump (MECS) that runs coolant through MG1, MG2, and the voltage converter.

 

Part 18D473 is the Auxiliary Pump. The purpose of the aux heater pump is to provide heated engine coolant to the heater core while in EV only.

[lolder]

After some internet research, I've found:

 

Part 8C419 is the Motor Electronics Cooling Pump (MECS) that runs coolant through MG1, MG2, and the voltage converter.

 

Part 18D473 is the Auxiliary Pump. The purpose of the aux heater pump is to provide heated engine coolant to the heater core while in EV only.

Good search! Where did you find the info?

[davidnyc06]

I put the information together after searching the two part numbers and reading a bunch of different posts.

 

I went to the dealer today and got it fixed. They wrote that they found "circuit #CHC01 chaffed near bottom of BJB. repaired circuit and reassembled."