Strange AC issues

[NurseSC]

I’m having AC issues with my 2020 Ram 1500 about 60K miles. No air movement out of the dash vents or windshield. Can only change the fan speed when ignition in run mode with engine off. Once the engine is on the fan speed is stuck on high. Some air movement out of the floor vents but it’s warm. Unable to change the temperature at all.

I’ve already looked at fuses and changed the cabin air filter. Took it to dealership. They couldn’t give me a diagnosis without requesting even more time and money. Any one with similar issues? Suggestions? Thanks!

 

[NurseSC]

I’m having AC issues with my 2020 Ram 1500 about 60K miles. No air movement out of the dash vents or windshield. Can only change the fan speed when ignition in run mode with engine off. Once the engine is on the fan speed is stuck on high. Some air movement out of the floor vents but it’s warm. Unable to change the temperature at all.

I’ve already looked at fuses and changed the cabin air filter. Took it to dealership. They couldn’t give me a diagnosis without requesting even more time and money. Any one with similar issues? Suggestions? Thanks!

Also already did the negative battery terminal disconnect to try to reset. Couldn’t get the 12” tablet to do a full reset as suggested on other forums. Software up to date. Thinking blend door actuators but looks like the entire dash will have to come off.

 

[NurseSC]

In case anyone else starts having similar issues - it was the AC and heater control module located under the glove box. Easy to access and about a $30 part.

 

[FastBlackRam]

In case anyone else starts having similar issues - it was the AC and heater control module located under the glove box. Easy to access and about a $30 part.

How did you diagnose it to be that module?

 

[NurseSC]

How did you diagnose it to be that module?

Asked dealership for the DTC codes from the diag I paid for and looked up the solutions using Chilton (free access from local library). All the codes led back to that same module. The module needs to be programmed though.


B2199-16 (HVAC) (active)
Battery Voltage-Circuit Voltage Below threshold

B11F3-15 (HVAC) (stored)
Right Panel Duct Temperature Sensor - Circuit Short to Battery or Open

B11F1-15 (HVAC) (stored)
Right Floor Duct Temperature Sensor -
Circuit Short to Battery or Open

 

[c3k]

Asked dealership for the DTC codes from the diag I paid for and looked up the solutions using Chilton (free access from local library). All the codes led back to that same module. The module needs to be programmed though.


B2199-16 (HVAC) (active)
Battery Voltage-Circuit Voltage Below threshold

B11F3-15 (HVAC) (stored)
Right Panel Duct Temperature Sensor - Circuit Short to Battery or Open

B11F1-15 (HVAC) (stored)
Right Floor Duct Temperature Sensor -
Circuit Short to Battery or Open

Nicely done. Of course...why couldn't the dealership figure that out???

What does it take to program the module? Is this something the dealership has to do, or can you do it?

 

[NurseSC]

Nicely done. Of course...why couldn't the dealership figure that out???

What does it take to program the module? Is this something the dealership has to do, or can you do it?

Right?! They would’ve eventually after billing for over $400 in diag fees alone (to be fair part of the solution called for checking wires behind dash before determining module bad so I get why they wanted more $$.) It’s not under warranty anymore though and I was only willing to pay one diag fee when I took it in.

I asked several local mechanics but none of them could program it. Dealership had to unfortunately.