KevlarCC

I hope this helps someone with A/C problems. It took a lot of research to compile.

If you are having A/C blower not blowing issues there are about 4 things that are easy to check.

1. The 7.5 amp mini blade fuse for the AC system in the fuse box on the driver's side on the side of the dash. There is a label on the cover to show you which one it is. If this is blown, the control panel for the AC will not light. If it lights, it is not blown.

2. The relay in the fuse box under the hood near the windshield on the passenger side. This also has a label that shows you which one it it but is is the biggest black box in the array. This relay sends available power to the blower when the ignition is switched on. It does not turn it on, it just send power to it. The A/C controls send a different signal to turn it on.

When you pull it out and look under it there are four prongs, two thin and two fat. The two small ones are hooked up to low amp 12 volts. That 12V is activated when the ignition is switched on. This energizes a coil which flips a switch to make the two fat ones connected. To test I put two banana clips with wires on the thin ones and touched the other ends to +/- on the battery. When I did, I heard a click (the switch flipping) and got continuity on my multimeter between the two fat blades. If it does not function you have to replace it. My dealer wanted $45 and had to order it but I don't have a part number.

3. Wiring harness under the glove box. If you lay on the ground in the passenger wheel well you will see the blower with wires connecting to it. Many people have reported melted connections. If you see melting, replace the harness. There is a service bulletin regarding this as well at: TSB 06-006

Example:



4. Control Transistor issues. The transistor circuit board that controls the speed of the blower motor has a large blade shaped heastsink connected to it. This heat sink is inserted into the blower compartment so that is has A/C blown over it to keep it cool. You can find it by looking under the glove compartment right against the floor carpet where your toes normally go. It is a white piece of plastic held in by 2 hex screws and there is a wiring harness connected to it. It is easier to remove the harness if you remove the screws and pull the assembly out first. Just pry off the white plastic to get to the circuit board. This is part number 79330-S0K-A01 and item 3 in:



Here is a bigger pic of it, this one is pretty corroded which can reduce heat transfer and fry the board:


The best hope on this one is that the fuse is blown. There are two pins on the circuit board that say "fused". Use your multimeter and check for continuity between these pins, if none then it is blown.

Here is a similar but not identical unit. The added graphic illustrates the fused pins:


The fuse is not user replaceable but you can hack it in one of two ways:

a. You can solder a wire across the fused pins. This is not recommended because it leaves the blower unprotected and the reason that it blew in the first place may fry the blower motor.

b. The other option is to solder a new fuse across the pins. I soldered two small wires to the blades on a mini blade 7.5 amp fuse and then soldered the wires to the pins. I stuck the fuse into the little cavity next to the board and wrapped everything in electrical tape thoroughly. This sounds hard but I had all of the supplies and I suck at soldering.

If it is not the fuse you can check to see if it is fried. To test is check the resistance between the three large soldered connections on the board. Check all combinations (1-2, 2-3, 1-3) and ohm ranges should be from 5 to 5000. If they are 0 or 100000, it is fried. If it is fried you have to replace it.

If all else fails you can try replacing the blower motor. It is part number 79310-S0K-A01 and it part number two in the picture above. It is held in by 3 screws but I never had to remove mine so good luck with that. It is tight quarters under that glove box.

Cheers!

punjistick

Brilliant info. Thanks a ton!

h_cam76

This was perfect... Thanks for the help

Morlock

I have a 1999 3.2 TL with the same problem. (Blower Fan does not work) There was no damage to the connector. The fuses and relay check out good. The blower motor reads 1.3 Ohms and spins freely. I found this link to a troubleshooting forum.

http://www.justanswer.com/honda/1q9r...-controls.html

In this thread there is a link to a .DOC file that gives a procedure to test the transistor module. I would just attach the file but I don't see that option.

oldsaintsfan

Thanks Kevlar for the great info. I will use this to test my control transistor. My problem is a little different in that the fan blows steady (even with climate control off) but the AC doesn't work. I did the climate control troubleshooting and got codes "I" (an open in the air mix control motor circuit)and "N" (a problem in the blower motor circuit). Not sure if testing the transistor will give me an answer, but it may help eliminate a possible problem.
If you have any info on my problem, I would really appreciate any help or guidance.

KJH

Thanks! You just saved me tons of $$$ to have this diagnosed at a shop.

When I hacked the fuse in the resistor circuit, I managed to get the old one out and found that it's a 2amp fuse.

03accurratl

Hello all,
I was hoping to find out the part numbers for both the
2position connector and 2 contacts for the harness which
connects to the Blower Motor in my 2003 TL.
My connector is pretty much melted, the wires are browned and the contacts are black; I want to replace them.
Your help is appreciated.

Thank You,
Dan

cottoi

KEVLARCC:

Just wanted to thank you a ton for the awesome to-the-point information. I am a chief engineer and I wish my people were as articulate describing our daily technical issues and more importantly, their proposed solutions, as clearly as you described the subject issue and solutions. In my case it was the Transistor Assy, the fourth possible reason you so clearly described. The fuse was blown and the resistance across the three described points were not consistent with the values provided so I decided to replace the entire assembly at a whopping cost of $43.00.

My AC is now kicking ass!!!

BTW, an interesting fact is that my car started to exhibit the following symptom before completely shutting down the blower: I noticed that the AC would stop blowing cold air after a while. It always did this after the car got warmed up. It acted as if the compressor would shut down after the car reached a certain temperature. I am not 100% certain that this problem is related also with the damaged transistor assy but as my experience has taught me to never rule out any possibility/risk and thus, I thought that it was worth mentioning. Perhaps the transistor assy went bad because of the same reason that kept shutting down the compressor. I will continue to monitor to see if the "compressor-shutting-down" symptom was also resolved with the replacement of the transistor/"resistor" assy. Will let you know!!!

Again, Muchas Gracias Bro!


Everybody: Please be aware that when searching for the transistor assembly, the major-chain-stores like Pepboys, Autozone, etc, have it listed as the blower "Resistor".

jlertdilok

Came across this thread after searching the internet for issues with my a/c and not blowing air...

I ran through all of the steps outlined by KevlarCC, and it ended up being the transistor fuse in step 4. Per KJH's reply later, I simply used a 2 amp fuse. I soldered it on, plugged it in and voila!, my a/c system works again!

All-in-all, I spent about $25 for the digital multimeter, soldering iron, solder and assorted fuses.

Granted, a new transistor would have only cost about $45, but for less money I still fixed the issue and also got some new tools.

Appreciate the community involvement, keep up the good posts everyone!

pimpTL

hey anyone know if the 2002 Accord plug will work? the wire colors are reversed compared to the TL.
anyone know if it will work if I just reverse the wires and splice it into the main harness?

Heres a pic left is TL right is Accord.



Also anyone know if it is OK to use a fine grit sand paper to take off the corrision on the blower power transistor?

724Bill

Awesome thread. My '99 3.2TL started having intermittent problems with the blower fan. It would stop working for a day or two, then unexpectedly start up again. I don't know how the fuse was failing in an intermittent way, but I soldered a new fuse in place following these directions and the blower works perfectly now. Thanks!

twistedwedge

I had the same issue with the blower quitting intermittently at random. It finally quit working all together. Turns out the plug connecting the blower was completely fried. I started with replacing the wiring and motor (which didnt fix it), and ended up having to replace the resistor as well. Works perfectly now.

I got all three parts (genuine Acura) on eBay for a total of 110 shipped. If anyone else is having issues I recommend replacing all three parts.

randomwalk101

Hi

Just wanted to say thanks for this excellent DIY. Saved me tons of money & time.
Mine issue turned out to be a blown fuse on the transresistor itself. A spare 10amp fuse, a little wiring and soldering and I'm back in business. I did bought the harness but mine was perfectly fine and no strain or kink so I left it alone for now

Tigger57

I just wanted to say thanks for the most valuable information. I was about to take my 2004 TSX to the shop but after eliminating the relay and blower motor, I diagnosed it as the blower transistor unit. No corrosion on mine but determined that the fuse within the unit was blown. I temporarily rigged a 3 Amp fuse paralled to the blown one and it worked. I have heard of others that used a 7.5 Amp and even a 10 Amp one but since I don't know what it should be, I went low.

I decided to buy a new blower transistor unit but a good hint, don't get it at your local Acura dealer. The one in this Chicago suburb wanted $97. I found the same thing for $53 plus $15 shipping and handling at www.acuraautomotiveparts.com. The part number is 79330-SDA-A01.

jenn-ay

Hi I read the threads above and I want to know what I should do first,the problem is in a 1999 Acura TL the heater and AC don't work the blower is not blowing. I checked my owners manual and changed all the fuses connected with the heater(under the hood,drivers side fuse box,and glove box fuse box)none of this corrected the problem so in plain terms that I can understand where should I look next for problem?

3.2TLc

Hey Jenn-ay, ya said that ya put new fuses in......were any of the old ones blown ?

Blower motor problems are common with our 2nd gen TL's. Most times it's the wiring connector to the unit being bad. Sometimes, if not all the variable speeds are working, it can also be the transistor pack for the blower unit.

If ya look under your passenger side, up behind the glove box, that's where the blower motor unit is located. First thing, take a look and see how the connector appears. There are other related posts with pics on this problem.

jenn-ay

Just wanted to say thanks, and none of the fuses looked bad but I replaced them anyway.Going to check the motor harness connection next and see if it might be bad, the blower doesn't blow on any speed or in heat or AC.

3.2TLc

Hey, I forgot to mention that our TL's have a self diagnostic set-up for the climate control system.

To utilize the feature:
Turn your car's key on, push the "Auto" button and the "Off" button on the dash control, while keeping both buttons pressed in.....the digital "Temp" indicator will maybe give you an "Error" code if it has a problem. The letter "N" would indicate an issue within the blower motor circuit. If no code is given and to return to the normal mode.....simply turn the key off.

Hope this may help, but most times ....it's the wiring harness connector melted or a faulty transistor pack.
An easy fix at less than $50.

Cyro22

I am just starting my diagnosis. Some thief smashed my window and stole the deck and now the fan motor doesn't work. No other damage is apparent and all the fuses are OK. Any ideas other than coincidence. I am going out to check the motor connector right now. Chris.

3.2TLc

Apparently you had a deck worth stealing !
Did the guy do a clean take.....or did he rip up some nearby wiring in the process ?
Best thing to do now would be to analyze the area a bit closer, good luck & sorry for your loss.

Cyro22

Deck was nice but quite old. It was a clean take. No real damage. Motor connector looks fine outside. Going to go check power at the motor, try the diagnostic and check the transistors. I might just be conicidence. Chris.

Cyro22

Results so far: diagnostics give no codes, resistor is 2.2K, blower motor is .9k, there is power at the blower motor connector. All connectors look good. I will keep looking. Chris

B.TL

Just had my wires melt.
Any idea why it happens?

3.2TLc

Under capacity or overloaded old original wiring harness for the blower motor.

Simply replace with a new one and check the resistor pack. Sometimes cutting and properly splicing the blower motor's connector may work.

B.TL

Thanks. Just making sure there wasn't something else I hadn't checked. On the bright side it didn't fry my blower and I figured out how to replace my in cabin filters.
It's like the car was being cruel to be kind.

Cyro22

Turns out it is the blower motor. I slammed the hood and it started working, although slowly. I am going to take it out and clean up the brushes if I can. I did that once on an old honda and it was a free fix that lasted for ever. Chris.

3.2TLc

Did you try jumpering the motor with direct 12v ?

This is to bypass the switch, relay, resistor pack, and a bad connector. With the resistor being bypassed, the motor should run at full power if good. The problem many times is with the connector itself or a faulty resistor pack.

Cyro22

First I had jumpered it with 12V and it did not work. Then after slamming the hood it started working, but slow. I took the fan motor apart to fix it but the commutator on the motor was almost completely worn away. A new fan fixed it up. The resistor pack looked fairly new so it must have been replaced at some time by the PO.

iamritesh

The blower would work intermittently on my 2001 TL. It had some sort of loose connection at Blower motor connector. Now it is completely dead.

TSB 06-006 describes my problem. I looked underneath the glove box and noticed that the blower motor connector is burned. Unfortunately i am not able to unplug it from the motor. How do you unplug it? i.e. remove terminal from connector. Attached are the pics to the part.

I think i have to replace the subharness for blower motor i.e. Honda part # is 04321-S0K-A00.

3.2TLc

The original blower heater harness is a weak spot on our TL's. The dealer's sell an updated heavier harness to replace the burnt ones with. Buy the new one, check over the connector and it'll help you to better understand the old harness removal. The original connector is probably brittle from the excessive heat, but hopefully the motor is still ok. May have to pry and pull ?

aameetsha

04 TL - Blower wont turn off and running at steady full speed. I have I, G, C, N code, Per forum comments, replace blower motor resistor yesterday and controls started working. However in 24 hours, Blower has stopped & lost controls again.

If I use old resistor, I get same old problem...meaning nothing wrong with the blower. Did I fry the new Resistor. Is there any other issue causing the resistor to blow

aameetsha

04 TL - Blower wont turn off and running at steady full speed. I have I, G, C, N code, Per forum comments, replace blower motor resistor yesterday and controls started working. However in 24 hours, N code is back and lost controls again.

This time, blower wont start at all. If I use old resistor, blower starts with no controls...meaning problem is with the new blower resistor. Did I fry the new Resistor. Is there any other issue causing the resistor to blow

TLinMN

Ok, so I'm in the middle of the blower harness fix. I don't know if there's another issue yet or not because I'm not done. The connection to the blower motor was black and burnt up. I'm trying to connect the "new" blue/red wire to the 5P resistor and I can't get the female connection on the wire past the male end inside the 5P. The male connection is at an angle . I can't get the wire end (female) to connect and it won't get in behind the male. What am I missing? Doing wrong?

TLinMN

Quick update...I feel pretty stupid, but I'll blame it on the eyes gettingold. I was able to get the red/blue female connection to fit properly in the 5Pterminal.



Now, everything is re-connected and the blower is still not working. Ichecked the fuses prior to starting and they were fine. The only thing I canthink of is the connection at the blower. The red/blue wire on the old harnesswas burnt pretty bad at the blower. It was brittle and I had to"pick" a couple small pieces out from inside the blower connection.How do I check to see if the blower is ok (still able to make a connection withthe new harness)? It fits fine right now -just don't know if it's"live". Or, is it the resistor?

3.2TLc

You could try bypassing the entire electrical circuit and directly jumper 12v to the blower motor to test if it will run.

1999BLK On BLK TL

Help, I have had a very bad problem with my Blower motor and a/c controls stopping working whenever I hit a bump in the road or sometimes if I shut the car off for a few minutes and start it back up to leave again the controls will be blank and the blower motor will not work. Every single time it happens the ABS light and TCS on the dash comes on. But if I hit another bump (sometimes it will start working again) The ABS and TCS lights will go off and the controls an blower motor will start working again... I have no clue why these are linked but it is no coincidence because when the ABS light is on I have no air. When it is off I have air... Any input would be great and help me out a bunch. It is my wifes car and she has had to drive mine due to the problem. Thanks Daniel

Gobba

If I've changed motor, resistor, harness, fuses. What are the chances it's the relay?

3.2TLc

Welcome Gobba !!!
While it's a common issue for the blower motor's wiring harness connector to melt and sometimes take out the resistor pack, normally the motor's still ok....but if ya replaced everything along the way, try checking the climate control's self diagnostic feature. Ya could swap another similar relay to test the blower motor's relay.

craigmax929

I'm at a complete loss TL family. I've replaced the relay under the hood, resistor, blower and blower harness to no avail and it's not throwing a code by pressing AUTO and OFF on the climate controls. Is time to go to an Indy as fall is just starting here in Indiana? Any help will be greatly appreciated. Thanks.

ANDREAR2

Hello- 2004 Acura TL Aspec. Had AC compressor replaced and AC recharged. AC stopped blowing cold a few months after that and fan remained on blowing hot air....read this.......bought a new transistor, and it fixed it, for about 30 mins!! Then, it went out and with that transisitor connected it doesn't blow any air at all.

Put the old one back in and it blows on high all the time. So...either this second transisitor got fried, or there is some other issue. Any ideas?

Before I go buying another transisitor, can someone maybe help me figure out what else it could be?