Heater failure

I have a major heater problem.

I have heat on the Drivers side 2 vents, it's blowing cold on passenger side. I had it at the dealership 3 weeks ago for this problem, they say they duplicated it, it was throwing a code so they reset it. It work when I picked it up. Yesterday I needed heat in the morning and I now have the same problem again. I have an appointment at the dealer for repair again. I suspect I'm in for a long drawn out process.

Has anyone experienced this issue? Is this the start of the dreaded evaporative cooler issue I'll be dealing with down the road?

It needs one of the temp blend doors replaced. Your ford dealer are idiots it is easy to diagnose that fault especially with a factory scan tool.

jdub.csu said:

It needs one of the temp blend doors replaced. Your ford dealer are idiots it is easy to diagnose that fault especially with a factory scan tool.

Click to expand...

Thanks Man...........I'm on my way to the dealer now.

The dealer put a blend door actuator on order. Now I'm just waiting.

Still waiting for that blend door actuator October 6th. Must be a run on these.

Still waiting on parts, I wonder how long?..........Good thing it's a heat wave this week. Although this morning it was 38deg it was still comfortable for the most part with heated seats on.

Mustang being so popular they don't have enough spare parts for repairs I would say.
I would ask for a whole HVAC control box replacement.

jasonstang said:

Mustang being so popular they don't have enough spare parts for repairs I would say.
I would ask for a whole HVAC control box replacement.

Click to expand...

Well, the HVAC system is popular for sure.

Blend door actuator came in so I scheduled the install on this past Tuesday morning. They had the car from 0800-1700 and the blend door actuator didn't fix the problem......Told me it blew hot air for awhile then stopped. They are performing more diagnostics and are leaning toward replacing the module.

They have the car again and I have a loner Ford Fusion, at least the fusion has heat, it was 31 Degs this morning on the way to work.

Had an issue with the heat not working in my last Mustang. Turns out that I had a coolant leak from the factory :doh: They had to order a replacement hose that took a week to come in, but I guess it made the coolant so low that the car didn't have enough coolant to fill the radiator core, but not low enough to trigger the low coolant light (the dealer actually got the low coolant light when they took it out for a test drive to diagnose the problem!).

The the opposite problem happen to my Mustang for the first time yesterday on a unseasonably warm day. With the A/C turned all the way cold the drivers side vents blew ambient temp while the passenger side blew cold. If I changed the A/C temp from cold to heat they all seemed to blow heat.

Pretty much, anything having to do with heated or cooled air seems suspect on the S550s. :(

DR_ said:

The the opposite problem happen to my Mustang for the first time yesterday on a unseasonably warm day. With the A/C turned all the way cold the drivers side vents blew ambient temp while the passenger side blew cold. If I changed the A/C temp from cold to heat they all seemed to blow heat.

Click to expand...

Sounds like a new evaporator is in your future.

Update: After a full week in the Ford repair shop and after replacement of the Blend Door Actuator with no-joy, they say the Front Controls Interface Module (FCIM) was the culprit for all my heater problems. Removed and Replaced FCIM and ran PMI on system. Heat is flowing out of all vents as advertised. I think they may just have this fixed.......time will tell.

Well she started blowing cold air on the passenger side again this morning, I may have used the heater maybe 4 times in the 6 days since they retuned the car last Thursday.

I'm hoping to get a diagnoses from the dealer in the AM.

Funny thing is they gave me the same loaner car back to drive so I get a chance to burn that 1/2 tank of gas out I left them when I turned it in last Thursday. Lol