2015 Honda CRV A/C and Blower Motor Troubleshooting

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Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC.

[@SuperSecretSquirell]

I had a good a/c repair this week. It was a comeback after having nearly all components replaced due to a compressor failure, so I figured it was going to be a cluster to figure out. While I was checking power and ground for the clutch I happened to move the high pressure cutoff switch wiring a bit and the compressor kicked on. Ended up de-pinning the connector and found one contact had almost no tension on the pins. Of course we can't order the terminals and can only get the whole harness, but I managed to get the contact tightened back up and got it working like a champ.

[@nicholaswalsh3016]

Best automotive teacher on YT. Really great practices. Cheers.

[@wandering_satellite]

Hi Mr Danner ! I have a "little tip" for everybody. When you're working on an A/C system, and have several components OPEN during the repair, you can use -Laboratory Conical Stopper Bungs- to protect the components and prevent any rough sh*t to enter these components and maybe end up with a catastrophe (doesn't need much of sh*t to damage a compressor). These Laboratory Conical Stopper Bungs come in many various sizes, and mostly made of rubber or silicone and are really cheap. You can cut them shorter if you need to. They are very useful when you're not working on NEW COMPONENTS which quite often already come with protection caps. Now, if you work A LOT on car A/C systems, then DON'T THROW AWAY THESE CAPS that often come with new A/C parts ... these caps are very handy when you're dissassembling and reusing old parts which are still fully functional, and when you want to do a CLEAN JOB. As always! GREAT VIDEO! 2 thumbs up!

[@martinsmartinsautobodyandr6740]

It’s funny I came across this video and I had to watch it through. I have a 07 Colorado in my shop now that the customer complained no ac. First I checked fuse and relay then hooked up my gages and hi and low was fine. He had mentioned that his mechanic removed some stereo equipment…so I pulled the controls out and what did I find…… the ground wire coming out of the controls with a but connector going to the metal brace underneath the glove box, which is supposed to be going to the blower motor resistor/ transistor. What an easy fix. I did order a new wiring harness for it because I don’t like sifting through other people spaghettini messes. Since you know I’m in Dover Pennsylvania ….this is a new customer that found out about me somehow and he is in Harrisburg. Not that far but word of mouth is great. Keep up the good videos.

[@ScannerDanner]

How did you watch this? It is unlisted until tomorrow. Please let me know

[@kc360awareness]

Is KZbin suggesting your videos on “preview black market”? That’s crazy.

[@ScannerDanner]

@@kc360awareness who knows lol

[@PistonShack]

I have seen the same problem on excavators before when faulty blower motor circuit won't allow AC to turn on and run. Great, consistent diag! Thanks Paul and Celeb!

[@spelunkerd]

Another inspiring video! It was so interesting to see the ground voltage fluctuate in time with the high frequency current draw of the motor. Of course, the current spikes occur at a moment when motor impedance sags down. So the voltage divider math for fixed downstream ground resistance gives higher voltage spikes on that outgoing ground wire. Add in extra current from a failing motor with no back emf and you magnify the effect. I especially like the way you spin an every day case study into a rich teaching moment. Now, to figure out how that downstream ground control works....

[@Glenn_123]

Paul - Thank you so much for doing this video. This is so much more then just a blower motor. I had ZERO idea that would have affected the pressures. So many different thoughts and concepts. I can not thank you enough and how much I appreciate your videos and your work!!!

[@ScannerDanner]

Thank you Glenn!

[@robertmedina6875]

Awesome content Paul and Caleb! I also ran into the mouse issues on 2008 JEEP COMANDER! You definitely know that mouse smell! Thanks for taking the time to scope the blower motor!!

[@kc360awareness]

Just had that same scenario last week on an ‘07 Pilot. Customer complaint was “AC not working, I think it’s low on Freon”. In reality it too was a blower issue…. Communication with your customer is key, it could save a ton of hassle on a more complicated issue. Turned out to be a bad blower transistor. The only way I had confidence in not condemning the blower motor was the use of a scope and amp clamp. Thank you for teaching us these techniques. Bonus Comment - used the scope and amp clamp to diagnose a carboned up VGT turbo on a Cummins engine a church bus. Shout out to ole Bernie Thompson for guiding me through that one!

[@labrat6910]

Always learn something new from your videos.Thank you Paul.

[@blake8297]

I love Caleb's down to earth questions

[@johnlenoir1023]

Thank you so much for explaining and teaching the ways of this automotive world I appreciate all of the videos that y'all make and love it please continue thank you

[@richardmitchell7836]

No, THANK YOU PAUL!! I have improved my diagnostic skills 100fold BC of you and a couple of the other greats on KZbin ( you drove them up to meet "ETCG") GOD bless you and your family.

[@ScannerDanner]

great time!

[@Bwelsh1981]

I try to explain some of these fundamentals to people about current flow compared to Voltage . Etc. It's amazing how some people just can't comprehend it. This goes to show you what a Good Education is all about. Much Love to you Brother. 🤙

[@ScannerDanner]

Thanks Brian!

[@isalmankhan1]

Superb👍 Love your work SD😍 Just finished assembling dashboard of a 2022 Chevrolet Tahoe, customer complaint was bad smell from A/C vent's & when I removed the cabin filter found part's of a dead snake, that got inside nobody knows how😉 It was a challenging one, had to use lot's of products cleaning & killing the bacteria inside the entire assembly, BTW the GM dealer here refused to take the job😉 Thanks for sharing SD, perfect time for these lectures, Love them😍 Stay Safe & Blessed Danner Family❤

[@salty_cracker_]

Thank you for taking the time to help others.

[@cullenmiller8170]

I thought using the amp clamp was a good teaching moment. I should have done that on my Rv furnace last year. The blower motor wasn’t coming on and kept the heater off. I found a bad solder joint in the board. It worked like a champ after the fix, but a month later the blower motor went out. If I had used an amp clamp during my trouble shooting I would have realized the motor was drawing to many amps and therefore caused the failure on the board. Thanks for all your teaching Paul.

[@salvadorgutierrezr5914]

Thank you for filming for us son Caleb and thank you Scanner Danner for always teaching us , God bless you both and family 🙏👍👍👍👍👍✌️

[@ScannerDanner]

Thanks for watching!

[@salvadorgutierrezr5914]

🙏 and happy Sunday Scanner Danners

[@Paul1958R]

Caleb/Paul, Great video, case study, diagnosis, repair and education - thank you! Paul (in MA)

[@Hesthegreatest1]

I just changed a blower motor on a 2017 Honda CR-V a day before you posted this ! Load tested the wiring with the fluke 289 just to be sure and then changed the blower motor and it worked like a charm. Btw if you don’t have a fluke 289 I highly suggest it for any Technician that specializes in troubleshooting wiring issues.

[@richardarmstrong2033]

Hey Paul, long time viewer under a different screen name. I got to say this is one of those videos you put out that is a lesson in itself that helps everyone trying to get in this field should watch and digest. It blends together so many concepts that it would take forever for me to expand upon. If I was teaching this could easily be a 10 hour study. Sometimes we see a video and it's like ok I get it. This one is different, at least for me. After 40 years working in the field I saw what was a natural progression that for the average viewer may be interesting but to a seasoned pro this hit all the marks.

[@ScannerDanner]

man, thank you so much! I have to remember this comment as I look at the crappy stats for this video for the first few hours of a release. There is a lot here if one is able to recognize it and I appreciate so much that you do. Thanks again!

[@ACOnetwork]

That was great description for blower motor failure 😀👍

[@glennwoodall4612]

another great video i liked the way you used the scope to confirm your diagnosis ,i suspect that a lot techs would do a prelimary check and then take a guestimate that it was the blower motor fine if it is but what if it is not ,your method confirms this ,i know a lot techs who have never used a scope but i believe that this the way to do diagnosis but a lot dealers just want a quick answer and techs have to be efficient and thanks for teaching a old dog more tricks

[@richard1835]

Thank you Paul for another great video. Thumbs Up

[@donniejohnson7499]

great video Paul Danner!!!

[@JimmyMakingitwork]

Funny, I've done 3 blower motors this week, 1 Honda, 1 Kia, 1 BMW and your blower motor video pops up...small world brother! lol

[@advancedleveldiagnostics]

Thanks Paul nice video! You clearly see a bad brush in the waveform, as the current keeps dropping to 0amps.

[@dtandfam8100]

Love the explanation on that gnd circuit. Was looking at that gnd voltage waveform rise with current and was thinking 🤔 is that a bad ground? But then your explanation of the amperage rise beyond the circuit design. Painted the picture for me, how the gnd circuit is the variable load/resistance. Thank Danner's! Awesome video

[@ScannerDanner]

exactly! In class with my students (and I have this recorded), I talked about a case study I did, having 5v on a fuel pump power feed wire from a frozen electric motor that was drawing 3 times the normal current flow. The power feed wire actually became the resistor in that circuit! Just another variable when it comes to troubleshooting and thought this was a good one to emphasize this concept. Thank you!

[@MetalMilitia072583]

Thanks for the detailed video! I checked my fuses first then watched your video, don't have your equipment but gave the motor a good smack and it started working.. i let out a good laugh

[@dhavyp]

Dawg, bless your soul. I had the exact same issue happening in this video and like you said you smacked the fucker so I thought "fuck it let me see what happens." BOOM, back to life in three seconds 😂

[@samodelkin3539]

Hello Paul. The reason for the ground to be high is the transistor in a ground side and they have a voltage drop internally. Great job. Like your videos. Thanks !

[@ScannerDanner]

Absolutely and thanks for the reminder. I'm not sure that I realized until the end of the video, that it was transistor controlled. But I've seen the wire itself do this same thing with excessive current

[@JOHNSUE28]

Danner, I watched this On Aug 10. On Aug 8 you should of been with me for my 2017 Pacifica, No A/C. I found the Compressor Clutch Coil failed. And it was a R1234a system. Interesting repair. You would of loved it.

[@fenceman53]

Goodbye to the old simple blower motor resistors. You had a good run

[@ScannerDanner]

🙂

[@fascistpedant758]

I remember looking up Ford's procedure to replace a blower on a mid 70s LTD back in the day. It was to locate a mark punched into the inner wheel well and measure a given distance right, then down, then back left, then back up, and cut a "door" to access the blower. So, yeah, they're usually easier now. They no longer require a cut off wheel and a welder.

[@ScannerDanner]

exactly! Some of these older cars absolutely sucked to work on

[@roseelectronics4582]

I learnt big time

[@jamesgoularte8460]

you can pull code with the right sequence in a/c button and the cabin filter check

[@orfeous]

Yes, i love these AC videos! Do you remember that i asked you about my concerns with the ackumulator/receiver/dryer on my system that had been open for a longer period? I repaired/replaced the short line that was bad. No visual signs though but the R134a was blowing out from it :) I had my car at a workshop and they did AC-service.. vacuum, leak test, pressure test, refill gas, oil and dye. Everything was OK. System sealed. So my repair was a success. Dont know about the ackumulator dryer media though if its consumed or.. i guess the time will tell? But... my compressor clutch does not want to engage. It has been like this before the leak as well so it isnt a new thing. Did some quick diagnostics with my scantool to view some relevant parameters. My suspicious its ac clutch relay, clutch wire, clutch coil/plate, high pressure pressostat, pressure guard.. I tested the 2 pin pressure guard today and it has continuity installed, could really not reach and see inside the connector on the high pressure pressostat so couldnt test it.. i tried but dont know if i was able to get connection with the probes. No beeps when i tried.. but i could been probed the "air" :) i might need to unscrew it and test with the risk of then have a leaking o-ring since its used. ive pulled up some parameters with scantool and it seems that the ac button on/off are working and the ECM sees the signal. AC relay are also displayed on or off. but cant hear any click either from relay or clutch.. with engine on or off with ignition on.. are the clutch supposed to engage with ac on off button with engine off and ignition on? high pressure pressostat is reporting 670-730 kPa without compressor running.. outside temp reported by CCM 22 celsius, evaporator temp 34 celsius, cabin temp 32 celsius, condenser/engine fan speed 22%, desired cabin fan speed 90% please help!

[@ScannerDanner]

This one is all you. It deals with inputs and controls for the clutch. kzbin.info/www/bejne/gYXFnpqgdpWBb9U You'll need to research your system to find out how it is designed but it will be similar in approach to the types of testing you need to do. Voltage over resistance. Resistance testing is not accurate enough for these types if issues. Watch this video then we'll talk more. Deal?

[@orfeous]

@@ScannerDanner yeah I was just watching that video you are referring to when you replied :) i have done some research, watching videos, reading on the web and also my tests with my oem factory scantool and computer software with it. Tried the manual activation of ac relay but could not hear any clicks from inside cabin. I'll guess you need to be outside at the relay to be able to hear and feel it clicking. As I described it seems that the system gets all inputs correct. And something isn't correct at the outputs. Relay, coil or wire. Don't know about the high pressure pressostat and pressure guard. Volvo are naming them that. One 3 pin on the high side and one 2 pin on the low side. I've read in the service software that the cooling fan are controlled by both the engine thermostat and that high pressure pressostat. I hope I can measure the coil at the relay output to see if it's ok or not. Wouldn't that also verify if the wire/connector to the coil from relay is good or not? Output should be on pin 5 Sorry for my English, grammar, spelling and explanation. Words are hard sometimes :)

[@orfeous]

@@ScannerDanner 20 kOhm between pin 5 on ac relay socket and chassi ground pin 5 are the output for the relay. Sounds pretty high. I've only seen 2-5 ohms But that is with the connector unplugged and measured on positive pin at the coil and negative on compressor case. Engine/condenser fan does not start. Tried swap fog light relay with ac relay. No change. 12.7v on pin 3 and chassis ground. When I put the relay in its click so I believe its engaging. But the clutch/coil does not. Bad high pressure pressostat? Don't know how to go further with testing

[@Pablo_Automotive]

Nice job team Danner

[@MarioDallaRiva]

Paul, last week I did a scan on my Bmw. One fault: 9CB3: Front height sensor defective It would be so easy to just swap the component but as a disciple of Scanner Danner I did diagnostic tests before condemning the potentiometer. Diagnosis confirmed wiring ok - the signal arm on the sensor was toast 💪🏼 $CAD200 component confirmed needed and it fixed the issue. This sensor is used to level the Xenon headlights which is nice to have fully functional at night. Only problem? I somehow dropped a back probe tip with a red banana connector (AES Wave) end down the inside of the brake rotor vent 🤬 Took 45 frickin minutes to get the sucker out. A green man moment for sure. Bimmer owners: shoutout to FCP Euro I got the OE version of the sensor for $US48 plus shipping 👍🏼

[@ScannerDanner]

a green man moment indeed 😂😂 thanks for this comment, it means a lot to me on many levels and thank you for supporting what I am doing!!

[@MarioDallaRiva]

@@ScannerDanner Thank you, Danners for all the good you folks do for the community! 👏🏼👏🏼

[@HomeOrchard]

I had a similar problem on a recently trip in a 2013 CR-V. I had no tools with me so I made sure that all of the relays were seated. Some relays were loose. The problem didn’t manifest again. I did however change out the blower motor and the resistor when I got home.

[@nandor690]

Danner says “in a pinch” But I’ve been using a long extension to smack the evap blower motor in my Tahoe work suv for 6 months now. 🤣🤣🤣

[@ScannerDanner]

🤣 man, I'd do the same thing

[@TheOffroader7458]

Did you change the cabin filter just above the blower motor ? Good video by the way

[@htownblue11]

Cool discovery on the ground surge in voltage due to the motor drawing 26 amps.

[@rs1971camaro]

Good idea when changing the blower motor is to check cabin air filter for restriction if the vehicle has one.

[@HotRod-wv4vm]

That was a pretty easy repair. Motor was readily accessible.

[@robertnicholson8054]

Strange way of doing voltage drop to reduce fan speed. Good video as normal.

[@deathventure]

Got a very similar issue to mine. I do a little percussive maintenance at the glove box and it picks back up. I'll pull it out eventually and replace it.

[@ask43242flight]

Great tutorial. Though I didn't follow how you verify whether the blower has ground. Did you check the voltage between green and door hinge? @8:39

[@nickayivor8432]

Welcome back Caleb 📷 man Thank you Please as Questions .take care and have a great day Caleb 📷 man PRODIGY Sir ScannerDanner Thank you very much 👍 Take care and have a great day Sir ScannerDanner From Nick Ayivor from London England UK 🇬🇧

[@bltoth1955]

Good video. Always learning something here. Have you ever considered putting on a tutorial for the oscilloscope? I’ve got the Autel Maxiscope mp408 and I’m sure I don’t understand more than 10% of its functions.

[@ScannerDanner]

I have these 2 available here on YT This is on a Picoscope but it is universal in content. I have other scope stuff on my website too of course. www.scannerdanner.com/join-scannerdanner-premium.html Thanks! kzbin.info/www/bejne/bmKkeJWQmMx2kNU kzbin.info/www/bejne/pKWte4yeoNKFaqs

[@calholli]

Another thing I've seen on another channel ---- is you can put your bad motor directly to the scope, and then slowly turn it and you can see the dead spots in the motor.

[@gizmo1-boss959]

FYI...Just got time to watch this video. This blower motor appears to fit multiple auto manufactures and models. Looks exactly like one I just put in a 2008 Buick Lucerne. Finally some standardization of parts. Bought one from Amazon part number MAYASAF 700203 for 36.99... There is an application chart that lists everything from Acura to Toyota. Fit perfect in the Lucerne and better yet it works. Check it out.

[@georgerocks5191]

Not a question about AC, but no other way to ask question. About 3 years ago, you did a video "11 volts on sensor ground". It was a bad ground that drove voltage from the normal 5 to 11. Using the same logic, will a bad ground at the alternator cause it to overcharge?

[@isorozco511]

Customers arent smart enough to specify between ac/blower problems. They just realize no air equals a problem and us tech need to figure everything out from square one.

[@reallone5]

Hey Paul nice ac diagnose. What I found weird why did it not blow fuse with such high current flow ? What size fuse is on that circuit .

[@ScannerDanner]

Not sure Dan, didn't check

[@general23cmp]

I’m about to be on my third 2015 CRV blower motor. The first was replaced under warranty. Both started to get noisy and flow reduced. They aren’t very good.

[@ScannerDanner]

parts these days suck!

[@justinballard7242]

17:02 try a newer escape. Gotta take apart the HVAC case. 7 plus hr job I believe

[@danielmusat597]

So, the voltage drop to GND was due to a semiconductor command circuit, not a wire or contact, as far as I understand. Nice and simple one if you know what you are doing. Cheers!

[@ScannerDanner]

Yes sir, thank you!

[@prissylovejoy702]

Can one of those DYI diagnostic tools that you can get online help diagnose an AC problem?

[@ScannerDanner]

Lol no. You'll get the same stuff from a Google search with a code. Don't fall for that b.s.

[@MsFireboy2]

Thanks Paul. But $75.00 for a blower motor. It ain’t your daddy’s Chevrolet. I totally enjoy your videos and your teaching style.

[@tunafish3216]

I would try a drop of oil on the bearings one that blower motor.

[@ScannerDanner]

That wouldn't work on this one as when it stopped completely, there was no current flow, so it was not binding mechanically. Make sense? Not saying is wasn't a factor (mechanically binding) but just simply when the motor stopped with no current flow means it also had brush/motor contact issues

[@bobo11112222]

stepped resistors ok. PLEASE Variable Freq. Blower next video test module & motor.

[@thomascotter1057]

Ford explorer part 3? Any update on ecu?

[@ScannerDanner]

No sir, this went back to the other shop and last I heard (a few months ago) it was still sitting there so it's out of my control. But spend some time reading the comments in here, it will give you more confidence in my call. I'm as sure as possible that the ECM is the right call. It's always hard to be 100% on calling a module but I did everything I felt I needed to do to be sure, and the comments helped me feel ever better about it. This seems to be a common issue now on this model.

[@obsoleteprofessor2034]

I wonder why the blower resistor didn't blow. I just help fix a 2004 Odyssey with an identical circuit. With no wiring diagram, we figured it was an old school blower resistor. It had a blown fan resistor (far side of your diagram). When we took it out, seeing blades sticking into the airstream reinforced our thought that it was old school design. We replaced it and it blew again within minutes. AutoZone gave us another one and we blew that one too. After that we figured we were just throwing parts at it. So we threw a fan at it, another blower resistor and it finally stayed fixed. There are YT videos where people have taken the blower resistor apart and soldered in individual components (Digikey sourced)

[@fascistpedant758]

Always check motor current before plugging in a new resistor. But I guess you know that now.

[@obsoleteprofessor2034]

@@fascistpedant758 Thrice burned...

[@Turbotomass]

Going to need an electrial engineering degree to work on automobiles.

[@matthewzoelle9149]

Lol some of the newer systems are easier, some really blow. Ever replace a heater core on a 2017 Ford F-350?

[@gabinosanchez1313]

The tech didn't ask the right questions " might be becouse he was drunk" 😂 ?

[@MarioDallaRiva]

Sounds like stomach after Burger Thing 😝 Mmm, Whopper…

[@ScannerDanner]

lol for sure

[@kilnprabu]

How much do you charge for such work?

[@ScannerDanner]

I don’t charge at all for what I do anymore, but this would have been at least a half hour of whatever your shop hourly rate is. If this was a mobile call, I don't even come out to a place unless I'm getting an hour approval up front.

[@kilnprabu]

@@ScannerDanner so what the hour rate going in the market for mobile call or service

[@juancarloscrane8089]

I'm so glad your videos are getting shorter and down to business

[@ScannerDanner]

Depends on the problem at hand. None of that is intentional.

[@user-up7lj3lk2c]

You language is fantastic , where you come from? And what is your organal country?

[@ScannerDanner]

Pittsburgh PA 😉 (USA)

[@davidsummers2616]

Your picture and pictures covering the screen for your ground can’t see what it is

[@ScannerDanner]

What time frame? What ground? My meter ground?

[@simplemechanics246]

Does anybody know why these motors and resistor packs goes bad? Anyone? Ok, very simple explanation - never replaced pollen filter. Soon as dust gets in, it covers the surfaces and rest is only matter of time. I did not watch video, but I will soon. EDIT: 9:00 You can keep using the multimeter, just turn the blower on. If voltages drops, you have bad wiring, resistor pack, etc, If voltages remains 12.XV, you have bad fan. 13:20 that rise is highly possible damaged coil. Stuck on one position just burn the coil down. EDIT 2: You even did not check the pollen filter... and did not show how full packed is the motor....The next motor dies within year again, because you did not made full job! Sorry, but this is not acceptable Do not be angry on me, this is just education. Everyone have different attack angle and different methods. No need fäncy oscilloscope, just multimeter or test light and everyone can to do that. Still problem remains...not serviced car! Pollen filter should replaced every year. Some car have 2 filters and the 2nd carbon filter can remain for many years, but first paper pollen filer must be replaced every year! Extreme dusty environment possible it must be replaced even multiple times every year. All depends where you use your car

[@ScannerDanner]

The cabin filter warning is legit but this was not an airflow problem as to why this blower failed. Your theories are a little off too as far as the voltage drop testing goes. Excessive current flow can look like a voltage drop problem if you're only monitoring voltage. As I proved in this video.

[@simplemechanics246]

@@ScannerDanner Excessive current or not, the voltage measurement helps to proof the circuit integrity. It tells instantly what way is your problem. Sure, these smart drivers can fool any multimeter. Fool the test light load if you can. Problematic cars typically are older and there is resistor network. I seen many failed blower motors and all have only 1 common thing, excessive amount dust inside the motor. Same time the fan blades can look clean, nothing wrong there...