023 Lightning (Build 08/23) – No Heat / No Defrost Heat – Dealer says “failed heater assembly” (any insight?)

[Scorpio3d]

Dang $1462 for the diagnostic & R/R of the suspect part!

Let's keep an eye on this line item when more failures paid out of pocket come up!

Yeah, I was going to say “ouch” as well but I don’t think “ouch” covers it!

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[chriserx]

Guess it's to cover all of those missed fluid changes.

 

[GoodSam]

Recall 23C32, about missing solder joint for heaters did not apply to this job?
https://www.tsbsearch.com/Ford/23C32
And since the cabin heater also provides heat for the HV battery, it should be covered by the 8 year, 100K mile warranty.

Although the part # referenced below is different than RL3Z-18K463-A, Perplexity AI says:
"
You’ve got it right that, on the 2023 Lightning, the “cabin heater” is also the high‑voltage coolant heater that feeds the heater core used for both cabin heat and some thermal functions, and that has warranty implications.
Part number for the HV coolant / cabin heater
For 2023 F‑150 Lightning, Ford describes the heater as an “electronic cabin coolant heater” and also labels it “High Voltage Coolant Heater” in recall documentation.

• Component name: High Voltage Coolant Heater / Electronic Cabin Coolant Heater
• Component description: Electronic Cabin Coolant Heater
• Component part number (Ford): RL3H‑18E64‑BB

This is the liquid‑coolant PTC heater that provides hot coolant to the HVAC heater core and is the truck’s source of heat for the 2023 BEV’s cabin.
Dependence of battery system on this heater
Ford’s recall documents explicitly state that this electronic cabin coolant heater “is the source of heat in the 2023 model year F‑150 BEV for both cabin” (and defrost), i.e., it is the high‑voltage coolant heater feeding the heater core.
If that module fails, owners experience loss of cabin heat and windshield defrost/defog, and you would also lose that primary high‑voltage coolant heat source in freezing conditions, so your concern is valid: the same module is doing double duty.
There can still be other elements in the thermal system (valves, pumps, and possibly additional small heaters or chiller interfaces), but the main HV coolant heater doing the heavy lifting is this “electronic cabin coolant heater” assembly.
Warranty angle (8‑year / 100k EV component coverage)
Ford’s own FAQ and warranty guides state that the F‑150 Lightning includes Electric Vehicle Component Coverage: 8 years / 100,000 miles for the high‑voltage battery and “EV‑specific components.”
Those EV‑specific components are described as the high‑voltage battery pack, drive unit, and related high‑voltage components that are part of the electric propulsion and thermal management systems.
Because Ford itself labels this module “High Voltage Coolant Heater” and treats it as an EV‑specific high‑voltage component in a safety recall, there is a strong argument that it falls under the EV component (8‑year/100k) coverage rather than just the 3/36 bumper‑to‑bumper.
However, the final word is how Ford (and your dealer) interpret “EV‑specific components” in the written warranty booklet for your VIN; dealers sometimes initially code it as a “heater” under normal HVAC, but you can point them to the recall language that explicitly calls it a high‑voltage coolant heater and to the EV component warranty description.
Practical steps

• Quote the part number RL3H‑18E64‑BB and the description “High Voltage Coolant Heater / Electronic Cabin Coolant Heater” when talking to the service advisor.
• Bring a copy or reference of the NHTSA recall 23V‑688 / Ford 23C32 document showing the component name and that it’s the source of heat in the 2023 F‑150 BEV.
• Reference Ford’s EV Component Coverage language (8 years / 100,000 miles for high‑voltage battery & related EV components) from Ford’s FAQ or warranty guide.

Functionally, you’re correct on both counts: the cabin “HV coolant heater” is a shared heat source, and that gives you a reasonable basis to argue it should be treated as part of the high‑voltage / EV component system for warranty coverage."

 

[Balke]

Recall 23C32, about missing solder joint for heaters did not apply to this job?
https://www.tsbsearch.com/Ford/23C32
And since the cabin heater also provides heat for the HV battery, it should be covered by the 8 year, 100K mile warranty.

Although the part # referenced below is different than RL3Z-18K463-A, Perplexity AI says:
"
You’ve got it right that, on the 2023 Lightning, the “cabin heater” is also the high‑voltage coolant heater that feeds the heater core used for both cabin heat and some thermal functions, and that has warranty implications.
Part number for the HV coolant / cabin heater
For 2023 F‑150 Lightning, Ford describes the heater as an “electronic cabin coolant heater” and also labels it “High Voltage Coolant Heater” in recall documentation.

• Component name: High Voltage Coolant Heater / Electronic Cabin Coolant Heater
• Component description: Electronic Cabin Coolant Heater
• Component part number (Ford): RL3H‑18E64‑BB

This is the liquid‑coolant PTC heater that provides hot coolant to the HVAC heater core and is the truck’s source of heat for the 2023 BEV’s cabin.
Dependence of battery system on this heater
Ford’s recall documents explicitly state that this electronic cabin coolant heater “is the source of heat in the 2023 model year F‑150 BEV for both cabin” (and defrost), i.e., it is the high‑voltage coolant heater feeding the heater core.
If that module fails, owners experience loss of cabin heat and windshield defrost/defog, and you would also lose that primary high‑voltage coolant heat source in freezing conditions, so your concern is valid: the same module is doing double duty.
There can still be other elements in the thermal system (valves, pumps, and possibly additional small heaters or chiller interfaces), but the main HV coolant heater doing the heavy lifting is this “electronic cabin coolant heater” assembly.
Warranty angle (8‑year / 100k EV component coverage)
Ford’s own FAQ and warranty guides state that the F‑150 Lightning includes Electric Vehicle Component Coverage: 8 years / 100,000 miles for the high‑voltage battery and “EV‑specific components.”
Those EV‑specific components are described as the high‑voltage battery pack, drive unit, and related high‑voltage components that are part of the electric propulsion and thermal management systems.
Because Ford itself labels this module “High Voltage Coolant Heater” and treats it as an EV‑specific high‑voltage component in a safety recall, there is a strong argument that it falls under the EV component (8‑year/100k) coverage rather than just the 3/36 bumper‑to‑bumper.
However, the final word is how Ford (and your dealer) interpret “EV‑specific components” in the written warranty booklet for your VIN; dealers sometimes initially code it as a “heater” under normal HVAC, but you can point them to the recall language that explicitly calls it a high‑voltage coolant heater and to the EV component warranty description.
Practical steps

• Quote the part number RL3H‑18E64‑BB and the description “High Voltage Coolant Heater / Electronic Cabin Coolant Heater” when talking to the service advisor.
• Bring a copy or reference of the NHTSA recall 23V‑688 / Ford 23C32 document showing the component name and that it’s the source of heat in the 2023 F‑150 BEV.
• Reference Ford’s EV Component Coverage language (8 years / 100,000 miles for high‑voltage battery & related EV components) from Ford’s FAQ or warranty guide.

Functionally, you’re correct on both counts: the cabin “HV coolant heater” is a shared heat source, and that gives you a reasonable basis to argue it should be treated as part of the high‑voltage / EV component system for warranty coverage."

Thank you for this. I tried to get them to cover it under that recall too but they said I didn't have a recall for that even though my build date is in that window.

 

[Balke]

Here is another part number mark. Could help someone looking for repairs.

 

[ZSC100]

Thank you for this. I tried to get them to cover it under that recall too but they said I didn't have a recall for that even though my build date is in that window.

Man I'm sorry Ford wrenched you around on this. There were at least 2 more avenues to get this covered, but if you aleady paid you SOL.

 

[Balke]

Man I'm sorry Ford wrenched you around on this. There were at least 2 more avenues to get this covered, but if you aleady paid you SOL.

Yeah, SOL sums the whole situation up well. Needed the truck back too much to have it in the shop any longer.

 

[bc1]

Man I'm sorry Ford wrenched you around on this. There were at least 2 more avenues to get this covered, but if you aleady paid you SOL.

I've been watching here. Are these 2 more avenues already listed or if not, maybe they should be for future reference. Thanks.

 

[ElectrifyingMe25]

Your optimism has come at the right time. I was about to my breaking pointI, use my truck daily for work but have a backup van I am using. I do not think this dealership is going to help me out unfortunately. I also have them looking at a parking sensor that was under warranty that was supposed to get fixed and never worked right looked at, a state inspection and wiper blades put on bc why the hell not while its there. I asked if that was done and they said yes but I need to make sure they looked into the sensor. He seemed surprised that I wasnt giving him the go ahead to repair ptc heater. I can be pretty stubborn at times and really dig into things that arent worth my time but I feel are the right thing to do, this being one of them. Im going to make sure Ford does the right thing.

Can you talk with another dealer in your area. Some dealers don't have BEV technicians. Maybe this dealer has to subcontract the work out through a tech who normally doesn't work for them.
Maybe a different dealer will help you more.

There have been too many of these PTC heaters to fail in the Lightnings. Probably another reason they moved to a heat pump. The design is kinda cheap anyway. Although the printed PTC elements are PTC, they need an adequate coolant flow to protect the printed elements. See pictures below. It's Mickey Mouse engineering.

I went through the whole PTC heater failure a few months ago on my '23 XLT Lightning. Luckily mine was covered.

I had a very good dealer who had a trained electric vehicle tech on the payroll.

If the don't cover it, report the issue to the NHTSA. Tell them your window was fogging up dangerously prior to complete failure. That's exactly what mine did. And yes it's powered by 400V, and heats the big battery and inside cab and defrosts the windshield.

The National Highway Traffic Safety Administration (NHTSA) is:
https://www.nhtsa.gov/report-a-safety-problem

This is the official page where you can file a complaint online. Your reports help NHTSA investigate potential safety defects, which can lead to recalls or other actions.

• You can also call their Vehicle Safety Hotline at 888-327-4236 (toll-free) for assistance.
• The main NHTSA website is https://www.nhtsa.gov/, and it prominently links to the reporting page.

If they want to play rough, play rougher. The PTC heater design is half-baked. Its made by BorgWarner in Michigan, BTW.

 

[ZSC100]

I've been watching here. Are these 2 more avenues already listed or if not, maybe they should be for future reference. Thanks.

They were not, but the steps and progression are very important when dealing with FMC. The next step was to take it to another dealer and report only the problem of "truck won't pre-condition the HV Battery / bad charging performance" Then, if they asked specifics those would be carefully contrived answers. If this didn't work it would at least have increased the time in service,, after just 15days in service BEV customer service will (with approval and specific request) give a complementary 35k factory ESP. But there are a few gotchyas, one is you have to be able to drive/live with the problem for 2+weeks while the ESP is granted and becomes active. There's more details I'm leaving out, but sadly, these proven work arounds to Ford's terrible customer treatment may not work as good now that the truck is cancelled. Things like: in my state one of the acceptable solutions to a vehicle declared a lemon is for the manufacturer to replace the vehicle with a functional equivalent, This gets complicated when trims change, but now there isn't even a new truck that is equivalent . It's a sad turn of events all around.

 

[MountainAlive]

Is the PTC heater in a hard to reach location or basically under the frunk tub somewhere? Just wondering for years down the road (hopefully years) when I may have to DIY replace it. Does it also require a coolant flush when being replaced?

 

[ZSC100]

Is the PTC heater in a hard to reach location or basically under the frunk tub somewhere? Just wondering for years down the road (hopefully years) when I may have to DIY replace it. Does it also require a coolant flush when being replaced?

It's under the frunk tub back near the firwall, super easy to DIY replace, just pinch the coolant hoses before disconnection then top off coolant after running the heater for a few minutes

 

[Ragman]

Had PTC short on our 2023 XLT SR - needed to tow truck in, truck has 80,000 miles +/- not covered under BEV warranty. Cost ~$2,000 and took 2-3 days, main wait was on the pump/parts.

Considering it a wear item replacement more then weakness/failure, we were regularly running truck at -35 C on overnight routes at that time - the PTC was running at max round the clock trying to keep truck and battery warm(ish).

 

[ZSC100]

Had PTC short on our 2023 XLT SR - needed to tow truck in, truck has 80,000 miles +/- not covered under BEV warranty. Cost ~$2,000 and took 2-3 days, main wait was on the pump/parts.

Considering it a wear item replacement more then weakness/failure, we were regularly running truck at -35 C on overnight routes at that time - the PTC was running at max round the clock trying to keep truck and battery warm(ish).

You also could've got yours replaced under the EV Powertrain warranty, especially with the urgency of using your truck in the climate you live in. But I understand the urgency of getting your vehicle back and the the stress of fighting Ford. Sorry this happened; a resistive heater is not a "wear item". It should last the life of the vehicle.

 

[MountainAlive]

You also could've got yours replaced under the EV Powertrain warranty, especially with the urgency of using your truck in the climate you live in. But I understand the urgency of getting your vehicle back and the the stress of fighting Ford. Sorry this happened; a resistive heater is not a "wear item". It should last the life of the vehicle.

Curious if there’s a definitive part list out there of what’s considered “EV powertrain” for this reason. I agree that anything that has to cool or warm the HV battery is to me “Powertrain” but we’d need to know what the Ford lords say.

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