All right, we got a hustle folks, we fell way behind on our first car, for today should be something from chevy right here. Here she is for chevrolet, we've got uh should be an hvac control, module, yeah, controller heater, it says, and then i got the old, clear, hair firing up. She's fired up, let's go get this chevrolet and see. If i diagnosed it correctly, didn't bring you guys along with that, but they should find out if i'm a loser of gold.

What year is this thing? 2014 chevrolet gmc rather, and it's got no heat? Oh look at that. It's lit up today. Let's start this baby. Oh, she just barely started, hey, look it's working and this is the guy's complaint it works and then it doesn't - and last time i looked at it, it worked for about three seconds and then it quit.

So, let's uh pull it inside here, get a battery maintainer on it, see what it does. It turns off and then on and then off and then on and then finally we i mean we haven't pulled inside, so it only lasts about a minute eventually. Here it just flips you, the bird and says nope not today, and it's just about where it's at keeps doing this little business here and then, like i said, then it shuts off completely. I got ta throw maintainer batteries about spanked in it um.

So what it was doing, i'll tell you when i originally brought it in was, was just that the lights uh it seemed to be when it was extremely cold uh. Today it's about zero out a little bit below zero. The hvac would work, but only for about a minute, or so it would start flickering and flashing lights and, ultimately quit you can communicate with it. Even when it's not on now, you can communicate with the buttons they're a separate module from the heater module which lives in the passenger side in the glove box behind the hmi module the human interface module.

So it had a code stored in it essentially stating that the uh i'll get the code number that the 5 volt reference circuit was no longer being output. But what i noticed is when i looked at scan data it did not recognize ignition voltage. It was showing the supply voltage for the module only being like four volts. Therefore, the five volt reference you know, couldn't work and i checked the five volt reference circuit coming out of it and it was at zero that feeds all of the actuators temperature recirculation and mode.

So the three actuators in this truck run off five volts. So i unplugged them all which were the pain they asked to get to the five volt reference didn't come back to life. The scan data still didn't change, so i made a call on the module. We got power, we got ground and we have can bus going to it, and then we have a lin bus that goes to the buttons they all test.

Fine, so therefore it has to be a bad module. So long story short, the guy said: do it so, hopefully i'm right so come inside here. Let's set this down. I left this in here.

Why did i leave this in here? Oh because this was the power grounds, communication circuit, that i checked uh to be sure. Everything's cool and then let's take, let's just see if i can show you one more time, you don't flick the old key on here and often times like. I say this will work initially, but then within you know a minute or so it shuts down, but it just continually has this cycle kind of works kind of doesn't when it does light up, it will ramp up the blower motor, which it's not doing now so, But like i say, this is just the buttons that run over to this module here. This is the hmi module.

So this is your human machine interface and you can see the most data bus on that, so the usb data bus and then so anyhow, i don't have a lot of time. So, let's get cranking. I just wanted to bring you guys, along in case, i'm wrong, that we can go through and sort this out. I mean i could be if i'm, if i'm not right, i don't so.

This is your heater control module. This is what runs your heater and these chevy pickups. If this isn't it, i don't know, a good friend of mine always tells myself to ask myself that he says always ask yourself if what you think the problem is, isn't the problem? What's your next step, or he says something something along those lines uh, and so you try to think about that like before you pull the trigger on it. You know on this module if that doesn't fix it.

What are you gon na do next? You know, have you run all of those tests already, so, let's plug this in, we got downtown brown connector right here and then this thing is in a hell of a spot here, folks uh. This also needs to be programmed. What's up, oh girl, um uh. Let's see yes, that's gon na go with the guy that has the black or the blue chevy out there when we're all done with it.

Thank you all right. So what we'll do so that's plugged in and not programmed? I wonder if it still lights up up here, let's see - and it does look at that and it's not blinking, no more we're going to look in service data. I mean yeah because it's acting all stupid because it like just lights up everything, but the good news is it's no longer blinking. So let's look in service data.

It disappears to be stuck on now. It's probably because it's not programmed so let's do that. Let's get after it, oh, and how do you know that needs to be programmed any gm module that has that little symbol right there on it? It means it needs to be programmed so to do the programming we're going to be using our gm mdi2 and gm tecline connect now we'll plug this little guy in it should go pretty quick. I'm thinking i'm hoping i'm going to keep my fingers crossed, we're plugging in we'll get connected to it and then i'll look and see.

If i can find what code this old one was throwing, she is creepy crawling along uh. Well we're waiting for that. Folks, a free tip for you, if you're working on your chevrolets, uh and you're wondering when you're looking in scan data, you've, we've all been there where we see this data pin and we're like well what the heck does that mean, or what's it supposed to be Control module references: this is what you always want to remember: working on chevy, if you're looking at service data, find your control module references come down here, find your control module and then you can get the schematics for it, how to replace it and then, importantly, how To program it and set it up, or does it need programming so we come down? I think it's. The k33 module hvac scan tool information.

So on mine you know i'm looking like what is the battery voltage pit? Is that our five volt reference? Is it battery voltage and it tells you you know, scan tool displays voltage. This is current battery voltage and, like i say, with our old one, it was displaying about four volts. So um, you know and everything like you know, what is the enhanced defrost switch? You know on off, what's it mean? Well, this tells you you know and you can come down through and this is for every module on the car and then the important part is. We can also go through and say you know: how are we supposed to program this uh hvac module programming? It tells you not to replace the module unless you're directed to by bolton or service procedure, connect, scan tool go to sps or our tech line.

Connect um perform the control module program, follow on screen instructions. After that clear the codes you know boom and then the setup for the replacement component. If an actuator has been replaced, the following must be performed actuator calibration. Now in this particular one we did just replace the module, but i did have one of the actuators off when i was trying to get them unplugged to check the 5-volt reference circuit.

I unplugged the temperature module. I believe it was the temperature door and the driver's side foot well. I can't get to the connector and take the actuator off so once this is done, i'm just going to calibrate the actuators double checking scan data and adios, and this was the code we're fixing the b139503 control module reference voltage or reference output circuit low voltage. So your reference output is your 5 volt output out of the module okay.

We want to view that later it's done programming, we're gon na clear the codes and then we're gon na go through a key cycle and shut the key off. Wait. A few minutes all right we can see the hvac controller is now lit up like a christmas tree and it's no longer flashing. Then i got to go through the process of trying to get it put back in the dash.

Absolutely ridiculous. I'm going to log in with a scan tool here we want to go to module diagnostics, and then we want to find what was it: the k33 module right, k33 hvac control module and there should be a recalibration under here. Control reset functions, actuator learn turn ignition on which it is we'll hit, continue we're going to let it do its thing here, just to make sure from unhooking that actuator, that everything's cool and the programming went through fine took a long time took probably 10 minutes anyways. I would say, but we're gon na, let this zippy zap through there, then i want to go back through and just poke at some data, real quick.

I want to see if we show the five volts and we show battery voltage so right now we're at 13.9 volts and we should be able to see that on scan data, also all right, roger that clear, dtc's continue. We want to go back and want to see if there is any code stored in it, because we may have stored some codes in it. Uh no code stored. So that's good, so we're going to back back out and then we just want to take and look at some live data.

Uh, maybe maybe sensor data system data is probably where i was at and then oops there. We go battery voltage, 14 volts and then we should see ignition voltage which on which they don't show that under the control module references which i thought was odd - that's at 14 volts and then okay. They don't have the 5 volt reference listed on here. They may not the sensor data.

These were all at 0 volts before no, because those are all just temperature pits. Last time i did, i did it with the um all tell so the menus here, a little bit different for me. Okay, maybe it was the counts. I was looking at yeah because i don't see yeah ac permission, security data, anything so made.

The all tell was set a little bit different. I do remember looking at battery and ignition voltage and seeing they were both low and then was setting. You know obviously was setting this code, so anyhow, i'm good, i'm happy with it, slam it back together. So i'm not trying to gripe people and be a mr busypants about new cars, but i mean let me uh.

I just got to open and close this door to shut off the accessory power there. We go um but uh, you know cars are getting and this is old. Like say this is a 14.. So this thing you know some old technology compared to nowadays in the year 2022 i'll set your hmi module um and i don't mean to be a pissy pants.

But it's gon na get to the point where you're not going to be able to afford to drive your car if it breaks the average joe y'all say a guy just wants a truck. Well here you know here's! I don't know what this was. A couple hundred bucks - you got ta program it you got ta, diagnose it. This whole thing for not having heat turned into.

Like i said it's like a 400 out or deal by the time you pay a shop to figure out what's wrong with it. Ah, this sucks putting this thing back in there's a bastard to get in here. It sits up on top of the heater box. Here it has a little plastic, strap that holds it in and uh you got to take the bracket loose for the hmi module and then you just kind of just shove it up in here get this thing up by the way, but i guess what i was Saying is, you know, we're gon na we're gon na surpass the stupid level as far as what it's gon na cost, the average guy to fix his car fix his truck um, and i feel bad for some of these people, because it is just this stupid.

You know we're trying to get it, so he's got heat and and what choice do you have i mean you, you have to fix it. I mean either that or you just got no freaking heat i'll, show you where this sits here in a minute. But you know what are you gon na? Do i mean it's? Not it's not my fault, but i'm just trying to sympathize with people here a little, but the fact is the other day i got to get paid too. I mean it's not cheap, to be able to learn and know this stuff and and be able to diagnose it and fix it.

I mean there's expenses on my end too, and i can't wait to be out of this industry because it sucks, but it is what it is for right now. I'm gon na keep doing it and uh try to keep people on the road but oftentimes. I wish i'd picked a different profession, folks, to be honest with you, come on just hate being the bad guy, but come on baby can't get your freaking fingers in here i got ta go get a poking apparatus, you stand by. Let me show you, so, can you see? What can you see you guys can't see? Let me uh, let me wedges the light up in here there we go so right up there, so you see the black connector and the brown connector.

So this is the glove box area, there's the heater box and it sets right up on there and it's just held in place with a pointing apparatus. This snap right here this this uh plastic snap just goes over that clicks down into the heater box right there. Um and then the hmi module will sit up in this area, so i got her clicked in it's kind of a pain if you got big meat nugget hands to get up in there, but we got to get this bracket here. I'll show you so there's the bracket for the hmi module sits in this little groove right there.

So you got to take that bolt out and then there's a couple bolts, one right here and one right here: yeah right there and right there. So we'll get uh, get them put back in there and get the hmi modules slid back in and that just clicks, and then this is all glove box stuff. Just some of this car stuff's getting a little overwhelming to me folks, it's just it's super stuff - is super complicated for what it is or for what it could be. I suppose, like this, like trying to plug in a usb cable, uh uh there we go get it.

Whoops hang on you guys still with me. This is that hmi module trying to get this one plugged in that one's plugged. In now we got ta get this little guy over here where she belongs all this, so we can have our infotainment yeah baby. Remember when a radio just had two knobs whoa now you guys are out of sight.

Oh, how i long for the day of a radio with two knobs and a heater with a cable whoa anything fancy in here. We don't need to look at nope. No, i can't complain. It pays my bills, but there's oftentimes.

I wish i chose a different profession, but you just do what you know, but this stuff gets boring. I tell you: fixing cars, maybe just monotonous, just one after the next after the next the same crap anyways. So, there's that now we can put our glove box back in. Where is the screw anything important here? You can't see how covered up nobody like everybody calls your eyes.

You guys like to find stuff all right, i'm putting the screws in it. You guys don't put the screws to me and head in that comment section the question the comments, the concerns, let me know if you long for the days of the old chevrolet, where it didn't cost you an arm and a leg. I just rhymed that whole thing to uh fix your hvac when you could just change a resistor, a blower motor or fix a short or whatever it was. It didn't, involve a computer module, let alone two or three of them.

So let me know about that. In that comment section when you're down there subscribe ring the bell, the questions, the comments, you know what to do and just from our viewers, if i can do it, you can do it thanks for watching hey.