RAM 2500 – Code B11FC

[birchit]

Hi guys,

my RAM 2500 2015 Power Wagon has a issue with the HVAC and letting no warm air to the passengers.

Can you help? CODE B11FC - how can I fix this air flap sensor, and where is its position? I have the shop/repair manual, but I can't find the position or anything else about this sensor.

- AC works
- Cold works
- Vents works, because it react when I change from the floor to the window or directly on the passenger
- Fan works
- Circulating air works
- Thermostate works
- Cooling system works
- Hoses are okay and warm directly at the heat exchanger
- Flushed the colling system
- Did I forgot something?

I have no further idea what I should check. When I shut of the fan I feel that the warm air which cannot come through will be stopped somehow. Is that a tempature signal thing of the sensor? Who had this same problem already or can help?

Thanks guys!!!!

 

[olyelr]

Sounds like your heater core may be clogged.

 

[birchit]

Damn, that could be. But this will be big work to replace, right?

Thanks, olyelr!

 

[olyelr]

Start by backflushing the heater core and see if that fixes your issue.

 

[GTyankee]

does heat get to the DRIVERS Side ?

I have only been able to find 2 similar codes

B11FC-11 - Blend Air Sensor Circuit-Short-to-Ground
B11FC-12 - Blend Air Sensor Short-to-Battery

 

[markabby]

might be an easy fix...son had a similar issue on a durango...it was a bad mixing valve on passenger side. on his it was a small round module that would open or close for heat or cooling. On his it was easily accessible via under the dash near the floorboard.

He had a/c on drivers side, while heat came out of passenger side.

at least look at that before you go pulling a heater core

 

[EastWestHemi]

I’d just be happy it’s the heater core, the contractor installing my floors pulled into my driveway with a top of the line 2019 Chevy 1500 and dropped 2 quarts of oil on my concrete driveway. Catastrophic rear main seal failure just out of warranty. All brands have problems.

 

[birchit]

does heat get to the DRIVERS Side ?

I have only been able to find 2 similar codes

B11FC-11 - Blend Air Sensor Circuit-Short-to-Ground
B11FC-12 - Blend Air Sensor Short-to-Battery

No, not the driver side and the passenger side!

 

[birchit]

might be an easy fix...son had a similar issue on a durango...it was a bad mixing valve on passenger side. on his it was a small round module that would open or close for heat or cooling. On his it was easily accessible via under the dash near the floorboard.

He had a/c on drivers side, while heat came out of passenger side.

at least look at that before you go pulling a heater core

Thanks. But I have no heat on both sides. Everything works correctly but only the heat doesn't get through into the passender room.

 

[GTyankee]

When you grab the 2 hoses that go through into the cabin,
one should be quite hot, the other should be a bit cooler.
like what the guys mentioned in the videos

 

[birchit]

When you grab the 2 hoses that go through into the cabin,
one should be quite hot, the other should be a bit cooler.
like what the guys mentioned in the videos

Exactly that's how it is...but the differences are pretty less...

 

[PA Ram]

I had the heater core go in my old 2005 Ram 1500 and it cost me about $1k. I drove for a year or 2 with no heat, because I didn't know how to repair that myself and knew it was going to be expensive. Hopefully something simpler like blend door or bad module like others have said. Take it to a trustworthy shop and have them look at it.

 

[jbaflyer]

I have a 2016 6.7 2500 with a bad heater core. Cost to replace at the dealer 2500. I was too scared to flush with CLR let alone do an inline flush though the whole motor. I ended up disconnecting the two hoses and hooked up to extension hoses. Then I added a pump and white vinegar. I circulated through the heater core for 24 hours with white vinegar. It was near blocked when I started and had completely open flow at the end of 24 hours, it ended up working beyond what I expected and I got my full heater core function back after I was done flushing with the white vinegar I push through the dodge OEM coolant into the heater core to get out all the white vinegar, of course, doing a water flush first, then when the air Corps was filled with as much coolant as I could get in there, I reconnected the two hoses, and I had very little coolant to add. I had just flushed the complete system earlier had i not I would have replaced all the coolant as well. There are some good vids of guys flushing the core only with it in the truck if you search Youtube.

 

[birchit]

I have a 2016 6.7 2500 with a bad heater core. Cost to replace at the dealer 2500. I was too scared to flush with CLR let alone do an inline flush though the whole motor. I ended up disconnecting the two hoses and hooked up to extension hoses. Then I added a pump and white vinegar. I circulated through the heater core for 24 hours with white vinegar. It was near blocked when I started and had completely open flow at the end of 24 hours, it ended up working beyond what I expected and I got my full heater core function back after I was done flushing with the white vinegar I push through the dodge OEM coolant into the heater core to get out all the white vinegar, of course, doing a water flush first, then when the air Corps was filled with as much coolant as I could get in there, I reconnected the two hoses, and I had very little coolant to add. I had just flushed the complete system earlier had i not I would have replaced all the coolant as well. There are some good vids of guys flushing the core only with it in the truck if you search Youtube.

Thanks for that - I will try said as well, but for my understanding I don't get it because the inlet and the outlet line is hot and there are not much difference of temperature. When the heater core is blocked the warm water of the cooling-system can not circulate or better said bat circulate. So the outlet line should be at least a little bit colder....did I understand that correctly?

 

[nlambert182]

It doesn't necessarily sound like you have a clogged heater core (mine never threw a code) but IF you do, or want to flush anyhow... this is what I did. I recommend flushing with water only first....

When I flushed mine, the temp differences in the inlet and outlet hoses were not extremely difference by feel. The heater core doesn't always get completely blocked. The casting sand settles in the bottom of the heater core which is where the heat is pulled for the driver side, so unless it's completely blocked coolant still circulates and that outlet line will still be warm enough that you might not notice much of a difference.

I didn't see much of anything come out of my lines when I flushed the first or second time. I flushed mine twice because even with an air assist I wasn't removing the blockage. CAVEAT** I do not recommend the following for you, so if you do this do it at your own risk. I am only telling you what I did and what worked for me as I was anticipating (and prepared) to replace the core if this didn't work. If you're not willing to shell out the money in the event that something goes awry, don't do this.

To finally clear my core, I dumped in CLR and let it sit for 2 minutes. Immediately after I back flushed my core with fresh water for 30 continuous minutes to ensure that any CLR made its way out of the core. Then I flushed from the inlet side for 5 minutes, and another 5 minute back flush. I then bled my coolant lines with the banjo fitting on the top of the engine until I got a solid stream of coolant.

After that, I topped off the coolant (lost very little) and have had enough heat since to melt you out of the truck.

 

[birchit]

Hi guys,

i did it, finally.

I removed the dashboard - which wasn't as problematic than I thought. Only the one screw behind the coolling water expansion reservoir wasn 't seen very easy. So that took a little bit a time.

What I have done:
- Changed all: Heater core, evaporator, automatic temperature control, all four blend door actuators, temperature sensor behind the evaporator
- Heater core and evaporator have looked like new...so that couldn't cause the general heat problem in my eyes
- Bleeding cooling system

Result:
- The blend doors worked, and warm heat was delivered - so everything fine. Then everything changed - nothing worked like it should.
- All four blend door actuators have the problem: To less power - I started the recalibration program AlfaOBD which couldn't start the process till today.
- Suddenly one blend door worked again and changed from defroster front window to centre air in MAR this morning, but no changes possible - recalibration will work, but during the process you don't hear any actuator starts working. AlfaOBD says process is correctly done.
- The defroster light for the rear window flashes constantly during driving, last week only the AC light flashes
- Somehow I have the feeling that the system is doing some kind of process, but I have no glue what and why and how I can complete it or stop it
- Pushing buttons or anything else has no effect in my 2016 RAM 2500 6.4L - like someone here suggested - that by the way
- Removing the minus cable from the battery for 15 minutes cleared everything, but the problems came back - by the way is there a difference if I remove the plus or the minus cable?

Do you have any ideas left, guys?

Thanks for your help!

 

[birchit]

Here are the last codes - I could delete:

B11C2
B11C5
B1058
B11CB
B11C8
B11CC
B11C9
B11C6

 

[birchit]

Can anybody help or has an idea???