3500 Ram With Some Heat

[Go-Fly]

Last year we were traveling through Cali and both computers went out in my Ram 3500. Had the 5th towed to Rolling Hills Casino and the truck to the closes dealer. Lost more money in the Casino then the cost of the two computers but, let's not go down that road. Here we are a year later and Ram sent me a letter that they have an update for the new computers or computer. Get the truck back from the update and the heats not working along with the windows. They get the windows working along with heat coming out of the dash vents only. Defrost and floor vent blow cold air only. At 10* outside, thats some real cold air. Now they say it's the heater core not the computer. It's like $2 large for a new core installed. I'll have them replace all the actuators behind the heat box and flush the whole system with new antifreeze for the fill. That's not a problem. The questions is, how can I get good heat out of the dash vents and zero out of floor and defrost if the core is plugged?

 

[Kachina26]

Last year we were traveling through Cali and both computers went out in my Ram 3500. Had the 5th towed to Rolling Hills Casino and the truck to the closes dealer. Lost more money in the Casino then the cost of the two computers but, let's not go down that road. Here we are a year later and Ram sent me a letter that they have an update for the new computers or computer. Get the truck back from the update and the heats not working along with the windows. They get the windows working along with heat coming out of the dash vents only. Defrost and floor vent blow cold air only. At 10* outside, thats some real cold air. Now they say it's the heater core not the computer. It's like $2 large for a new core installed. I'll have them replace all the actuators behind the heat box and flush the whole system with new antifreeze for the fill. That's not a problem. The questions is, how can I get good heat out of the dash vents and zero out of floor and defrost if the core is plugged?

Mode door issue, not a heater core. Not a Dodge guy, so not much on specifics for you.

 

[Gelcoater]

What year?

If you are getting heat at all it isn’t the heater blend door (my current situation)
I’m not to educated here. My issues have always been blend door or actuator, no heat at all.

 

[Melloyellovector]

Has to be mixer door. Cores either work or don’t or leak. No in betweens.

 

[DarkJuJu]

I have a close issue myself, I wouldn’t waste time with the actuators, you can open the glove box and see if it’s working or not, if you’re not hearing clicking. I have some heat but only coming out the passenger side, but never gets “hot hot”. The damn thermostat it’s close to $300 or $400 for the mopar part ( that’s just stupid), I would just do the flush first and hope and pray. I still need to do a flush too before laying out another $2500 for the heater core but I am in phx and we just haven’t needed the heat yet.

 

[X Hoser]

Last year we were traveling through Cali and both computers went out in my Ram 3500. Had the 5th towed to Rolling Hills Casino and the truck to the closes dealer. Lost more money in the Casino then the cost of the two computers but, let's not go down that road. Here we are a year later and Ram sent me a letter that they have an update for the new computers or computer. Get the truck back from the update and the heats not working along with the windows. They get the windows working along with heat coming out of the dash vents only. Defrost and floor vent blow cold air only. At 10* outside, thats some real cold air. Now they say it's the heater core not the computer. It's like $2 large for a new core installed. I'll have them replace all the actuators behind the heat box and flush the whole system with new antifreeze for the fill. That's not a problem. The questions is, how can I get good heat out of the dash vents and zero out of floor and defrost if the core is plugged?

Sure seems odd that they quit working properly right after the update! Does not sound like a heater core issue to me. Sounds like a mixer problem, and I bet they are electronically controlled by input through the computer???

 

[COCA COLA COWBOY]

Like others said, it's not the core. The problem is the tech doing the diagnose. Go to another dealership and be sure to explain that everything worked well until the moment they worked on the computer. I think you can escalate an issue with RamCare too.

If the truck isn't that old, I would look into a Lemon Law. My hearing is next month on my lemon law and I most likely will just go to Mark Dodge and get another new truck and get ready to do it all over again.

These manufacturers will eventually learn that they will need to put a product out that works or they will go BK with the lemon laws.

 

[Go-Fly]

What year?

If you are getting heat at all it isn’t the heater blend door (my current situation)
I’m not to educated here. My issues have always been blend door or actuator, no heat at all.

It's a 2018. I get alot of heat through the dash vents, even the vent for the back seat is hot. Ice cold the other two.

 

[OCMerrill]

I agree with Coca Cola Cowboy there is a programming issue. I have a 2018 2500 with about 90k with no issues. I am curious why computers would fail. I am assuming there are modulus involved that failed or the main PCM? It may have been programed for a different model 3500 without features you have.

I also say its more a tech problem at this point.

 

[timstoy]

Blend door issue. If you have heat in any position the heater core is not plugged.

 

[Bowtiepower00]

When you start the truck, and a few seconds after you shut it off, can you hear the blend door moving under the dash?

What computers were replaced, and what update was installed?

I would guess blend door or possibly the update didn’t load successfully and the computer is stuck in limbo. 18 has some slight differences from the earlier trucks as they transitioned to the 19 and newer gen 4.5 trucks.

As mentioned, I would try another dealer or try to find a reputable diesel truck repair shop.

I’m sure you have already looked, but check turbodieselregister and cumminsforum for fixes, if it has happened to another truck someone has probably posted about it on one of them.

 

[coolchange]

Isn’t the blend door What adjust the level of the heat and cold air mix? Turns the temperature to cold Or hot. Does it change? My ram is a lot older than yours. I’m sure the new ones are all servo actuated. But just in case, the heater diverter Doors in my ram are vacuum.
The blend door axle sticks out of the bottom of the heater box. If you can reach under there, you can find it and feel it cycling.
Obviously not a bad heater core. You can prove that easily enough with an infrared heat gun.
Last guy to touch it loses.

 

[Go-Fly]

When you start the truck, and a few seconds after you shut it off, can you hear the blend door moving under the dash?

What computers were replaced, and what update was installed?

I would guess blend door or possibly the update didn’t load successfully and the computer is stuck in limbo. 18 has some slight differences from the earlier trucks as they transitioned to the 19 and newer gen 4.5 trucks.

As mentioned, I would try another dealer or try to find a reputable diesel truck repair shop.

I’m sure you have already looked, but check turbodieselregister and cumminsforum for fixes, if it has happened to another truck someone has probably posted about it on one of them.

We were having problems with the engine running right. The dealer replaced two computers. Not sure what they did. Both were showing codes to replace. The update was for the DEF system and transmission issues. When I got it back, it paused before it would shift. They said it would do this for a few days and it did. The truck runs much better after the update, smoother but, uses more DEF. I can remove the glove box and see the actuator move from heat to AC and AC max when called for. Both hoses are hot, in and out of the heater core.

 

[lbhsbz]

Last year we were traveling through Cali and both computers went out in my Ram 3500. Had the 5th towed to Rolling Hills Casino and the truck to the closes dealer. Lost more money in the Casino then the cost of the two computers but, let's not go down that road. Here we are a year later and Ram sent me a letter that they have an update for the new computers or computer. Get the truck back from the update and the heats not working along with the windows. They get the windows working along with heat coming out of the dash vents only. Defrost and floor vent blow cold air only. At 10* outside, thats some real cold air. Now they say it's the heater core not the computer. It's like $2 large for a new core installed. I'll have them replace all the actuators behind the heat box and flush the whole system with new antifreeze for the fill. That's not a problem. The questions is, how can I get good heat out of the dash vents and zero out of floor and defrost if the core is plugged?

I'd have them explain how the heater core is capable of selectively channeling it's heat through the dash vents and not the others....while recording the idiot stammering out his BS answer.

Not sure where I'd go from there....probably the Chevy dealer.

 

[Go-Fly]

I'd have them explain how the heater core is capable of selectively channeling it's heat through the dash vents and not the others....while recording the idiot stammering out his BS answer.

Not sure where I'd go from there....probably the Chevy dealer.

I've bought new trucks starting in 1978. Sometimes I would by them 5 at a time. Never replaced a heater core that wasn't leaking. All my vehicles are serviced like clockwork. This just smells and sounds like bullshit. I don't mind having it fixed but, they returned it three times saying it was all fixed and it wasn't. All programing problems. Now it's the core? I'm looking to buy a new truck this year. This one will be fixed right before I trade it in. Who ever gets this truck will get a 10. I've never have had a Ford truck. Drove Chev, GMC for the last 15 or so. Funny story how I ended up with Ram.

 

[calkid]

Maybe they loaded the wrong "fix" to your particular computer?

 

[spectra3279]

Last year we were traveling through Cali and both computers went out in my Ram 3500. Had the 5th towed to Rolling Hills Casino and the truck to the closes dealer. Lost more money in the Casino then the cost of the two computers but, let's not go down that road. Here we are a year later and Ram sent me a letter that they have an update for the new computers or computer. Get the truck back from the update and the heats not working along with the windows. They get the windows working along with heat coming out of the dash vents only. Defrost and floor vent blow cold air only. At 10* outside, thats some real cold air. Now they say it's the heater core not the computer. It's like $2 large for a new core installed. I'll have them replace all the actuators behind the heat box and flush the whole system with new antifreeze for the fill. That's not a problem. The questions is, how can I get good heat out of the dash vents and zero out of floor and defrost if the core is plugged?

If it was working before the update, then it's the update thats broken.

 

[Kachina26]

I’ve seen a reflash fail before. Maybe that’s it? I can’t stop fixating on “both computers", you have way more than 2. Which 2 were replaced? The whole deal stinks.

 

[Go-Fly]

If it was working before the update, then it's the update thats broken.

Ya, I need to pump the brakes on this whole thing and go back to square one. It worked just fine the morning going in. I think it was 18* that morning. Picked it up just before closing and froze my ass off on the way home. They did get everything working once but, we went to dinner after picking it up, came out to the truck, stared it up and only heat through dash vents. Don't you hate it when you know things are going to go to shit.

 

[Go-Fly]

I’ve seen a reflash fail before. Maybe that’s it? I can’t stop fixating on “both computers", you have way more than 2. Which 2 were replaced? The whole deal stinks.

Not sure what the computers did. Dodge covered everything. I saw the invoice it was almost $20k. They paid for the update and all of the attempts to repair this heater problem. So what do you do with that?

 

[Kachina26]

Not sure what the computers did. Dodge covered everything. I saw the invoice it was almost $20k. They paid for the update and all of the attempts to repair this heater problem. So what do you do with that?

I guess take it to a competent tech, have them document the repair needed to fix the issue and go to small claims for whatever you’re out.

 

[Good Stuff]

Looks like if you pull the glovebox out you can access the actuator. See if it’s moving from hot to cold when you flip the knob. seems like the techs now are just parts swappers. They just throw parts at things without any diagnostic work. They don’t even follow diagnostic charts at my local dealership before they go straight to parts replacement.

 

[TimeBandit]

smack / tap the actuator with the plastic end of a screwdriver if you can't hear / feel it moving, as you change output positions from vent to heat etc, if that gets it going you need a new one.

If smacking the actuator with a screwdriver does nothing.. maybe it is not getting a signal to do something... as in update related?

The factory scan tool should be able to tell what is happening or being commanded to do something.

If the heater core puts out heat somewhere, and does not leak, it is good.