Installing the Factory TSB A/C Condenser Fan (DIY)

I recently installed the factory condenser fan that Mexico-equipped trucks receive by default. It was a bit involved, but nothing too complicated if you understanding wiring and have some patience. HUGE shoutouts to @caribe makaira and @Jeff Lange. Many know that Caribe is a wiring diagram wizard, and this case is no different. He has touched on what wiring it would take to get this install done several times over the years (in the TSB discussions) and so his info on that is what sparked me to start looking into it. After learning how it worked, and that the circuits to get it done wouldn’t be too difficult to access, I decided to get after it and investigate ordering parts. That’s where Jeff comes in - as always, when I ask, he very helpfully points me to the exact right part numbers, down to screws and wiring clips. He also saved me a significant amount of money by advising to build the fan myself (with all part numbers provided) vs buying the expensive TSB fan assembly. I’ll detail that out later.



Why would anyone want this?

Many people have complained about the air conditioning not being cold enough at idle: sitting at stoplights, in traffic, drive-thrus, etc. As many are aware, the Tacomas that go to the US and Canada only have a mechanical cooling fan, which is belt driven and fixed to a viscous clutch. These style fans are great for engine cooling, but they don’t move as much air at idle as a variable speed all-electric fan, which is a key factor in good air conditioning performance when the vehicle isn’t moving. The A/C condenser needs ambient air flowing through it to continuously remove heat for the best performance. As such, the more air you can flow through the condenser, the better. Idle conditions are where the mechanical fan suffers the most, since engine speeds are low and the vehicle gets no “ram-air” assist from moving down the road.

The trucks which are built to ship to Mexico, receive an additional cooling fan from the factory, which is an auxiliary single-speed electric fan, bolted to the core support in front of the right side of the A/C condenser. The A/C amplifier (essentially the A/C “brain”) decides when to turn the fan on based on many different factors (basically, when it thinks the fan should be on). The amplifier provides a relay ground to turn the fan on in these conditions. ALL Tacomas ship with the same amplifier programming, meaning whether you have a truck North of Mexico without the fan, your amp is still outputting the signal to turn the fan on.

My assumption for why this fan is only equipped in Mexico-destined trucks is that it probably is related to cost. Mexico is of course, not the only location in North America that has warm weather, however, the number of Tacomas that go there is significantly smaller than the number of US & Canada destined trucks. It would be a lot for Toyota to put that fan on every single North America truck, so it’s probably easier for them to skimp. Nobody knows the true reason for sure, but that is my hunch.

There is a TSB for the United States, which adds the Mexico-factory-equipped fan to the US trucks. It mounts the fan to the core support like stock, and provides a wire harness w/relay box that mounts to the left inner fender. The wire harness runs to the fan, hooks to the battery, and has a couple wires to run into the cab to hook into two of the dash connectors. The only way to get this TSB done is to complain about your AC “shutting off” at idle. Supposedly, if you complain correctly, the dealer will perform the TSB and install the fan. I considered trying but never got around to it. I drive a lot and am 18K miles out of the bumper to bumper warranty. So, I decided to DIY and see what happened.

Bottom Line

If you are perfectly happy with things as they are, this will probably not benefit you much. I am in a very hot area in Texas (100-110° regularly in summer), and even I don’t have much of a problem. Toyota does a pretty good job of bumping the idle enough when AC is running that air movement from the mechanical fan is decent. However, there have been times when I wish it were better. So if you have complaints at idle, maybe consider this if you’re handy. If you don’t have complaints and/or aren’t handy, don’t.

If you decide to do this, then hopefully my info should make it easy to understand.

Parts Needed/Suggested:

Fan Parts

I bought parts from Sparks Parts. They were on backorder and the order shipped around 6-7 weeks after ordering. I’ll list the price I could have paid on the complete fan, vs what I did pay on the individual parts.

• $568.25 - 88590-35050 - Fan Assembly

OR

• $161.21 - 16363-64080 - Motor
• $21.86 - 88453-60010 - Fan blade
• $114.88 - 88454-35090 - Shroud
• $0.52 - 82711-2B640 - Clamp, Motor Wire
• $0.27 - 90099-04117 - Screw, Fan to Motor; Qty: 3
• $0.86 - 90099-04119 - Screw, Motor to Shroud; Qty: 3

Total: $301.86 for fan parts.

There were other parts I added as well, and things I bought later that I should have put in the original order. But $301.86 is pretty clearly a better deal for 5 minutes of my assembly labor.

Miscellaneous Parts Recommended:

• 90119-A0078 - x2 - Bolt, for fan shroud to core support (M6-1.00, large loose washer built in)
• 36869-04010 - Cover packing (from TSB)
• 36869-04030 - Cover packing (from TSB)
• 36869-04040 - Cover packing (from TSB)
• 36867-04040 - Seal packing (for skid plate - does not work with TRD skid)
• 90980-11237 - Connector F (for plugging harness into the pre-assembled fan motor pigtail)
• 82998-12480 - x2 - Terminal, repair, with wire (for connector F connection to fan - 12AWG, crimp and splice your own wire to them)
• 82998-12870 - Terminal, repair, with wire (for AC amplifier connector (insert pin into connector)

Additional Miscellaneous Materials Recommended:

• Split loom (with white dotted stripe indicating heat rated, various sizes)
• Tesa or similar harness tape
• 4-pin relay and connector
• Zip ties (I like metal tooth style for strength)
• Coat hanger or stiff wire for pushing/pulling through grommet
• Creativity
• Patience

This is going to be a long post but I’m going to try to keep it as reasonable as I can while still explaining things. Since DIYers are unlikely to purchase the TSB wiring harness, the wiring work will likely be custom, and I’m going to leave a lot of that up to the installer. I’ll show what I did to some extent, but I built a custom fuse panel for my truck (for light bar, ditch lights, backup lights, etc), and so exactly how I did it is not going to be relevant for anyone else.


I’ll break it into 3 parts:

1. Tapping the AC amplifier connector (for relay ground - this is the control wire)
2. Tapping for ignition power (to actuate the relay when the ground signal from the amplifier is provided)
3. Fan
   1. Assembly
   2. Mounting
   3. Assembling fan connector, extending wiring
   4. Showing how I ran my wiring

Part I: Tapping A/C Amplifier for Relay Control (ground signal)

As I mentioned earlier, the A/C amplifier is the brain that decides when to turn on and off the condenser fan. In order to control the fan, we need to obtain the ground signal from the amplifier for fan turn on.

There are two types of climate control: auto and manual. I have auto, but many trucks have manual and I’ll detail out the difference in install. It is simply a different connector and slot you insert the wire into depending on which you have. No big deal.

No matter which climate control style you have, you will need to remove the glove box to get to the connector we’re working on. I’m not going to post photos, but I will briefly list the steps to help:


Removing Glove Box:

1. Disconnect battery
2. Slide front right seat back
3. Remove the floor mat (twist the little locks 90 degrees and lift up)
4. Remove the front right door sill trim piece (pull up)
5. Remove right kick panel (remove the thumb nut securing the panel, then pry the panel towards the console)
6. Remove the end dash trim piece (triangle-shaped) that inserts into the door seal. Use a pry tool
7. Remove the curved dash end piece on the right side of the glove box. Gently pull it towards the passenger front seat
8. Remove the radio trim (grab and pull gently)
9. Remove the trim above the glove box (remove the exposed screw where the radio trim was removed, and remove the screw on the right side as well)
10. Remove airbag from below glove box (remove 3 10mm head bolts, then gently pull on the airbag and use a flat blade screwdriver to free the 3 clips that allow it to unclip from the glove box)
11. Set airbag aside (don’t stretch the wiring, lean the airbag against something)
12. Remove the four remaining glove box screws and remove the glove box by pulling outward

Glove box removed: (photo credit @MisterKitchen )



This is what it looks like once the glove box is out. You can see the A/C amplifier connector in the red-circled area. Manual A/C has the one connector, automatic has 2. Now that the glove box is out of the way, we need to work on adding the trigger/control wire.

I’ll start with auto A/C. If you have manual A/C, scroll down to the manual section.

For automatic climate control (check out wiring diagram PDF I made “Condenser Fan (Automatic Air Conditioning” attached)



Find the A35 (28-pin) connector. Green circle in the photo below. It is the smaller connector and we are adding our wire to cavity 8. We know this because the diagram above says “8 (A)” and when you look at the A/C amplifier, it states (A) is connector A35.



Take a small pick or something and gently use it to pry on the horizontal connector lock in the photo above. The lock will pull outward just a bit. Insert the 82998-12870 wire in cavity 8.



For manual climate control (check out wiring diagram PDF I made “Condenser Fan (Manual Air Conditioning” attached) - skip if you have auto



Find the A14 (40-pin) connector. Red circle in the photo below. It is the only manual A/C anmplifier connector and we are adding our wire to cavity 16. We know this because the diagram above writes “16” next to the pink wire at the A/C amplifier.



I don’t have anymore photos for manual A/C. Reference the connector lock in the auto section above and follow the same procedure. Insert the 82998-12870 wire into cavity 16.

Running the wire

Tape up the wire and loom it or whatever you want to do to protect it. I put it in expanding loom and then taped the end of that loom. Then taped the loose wire to the bundle to keep from the one wire getting tugged out of the connector.



Wire is zip tied to instrument panel harness up to the main trunk that runs across the dash support bar.



Some photos running it behind the radio and instrument cluster. Way less intimidating than it looks. It is a lot of work for just one wire, I guess, but it’s worth it for smart computerized fan control. The zip ties are still long in the photos, trim them flush with flush cutters. I like Milwaukee for mine.



For the interior portion of this wire, I ended it with a good quality crimped spade terminal. It tucks into the left kick panel area.

This wire needs to go to pin 85 on your 4-pin relay. This is all I’m going to show. Run the wire through the firewall how you see fit. I went through the left side grommet.



Part II: Tapping for Relay Power (IGN 12V)

This is the wire that will provide power for the relay’s coil so the relay can activate when the A/C amplifier provides the relay ground to turn on the fan.

You can obtain this any number of ways. Fuse tap somewhere, you could get it from the small fuse box under the hood (hooked to large fuse box), etc. The Toyota TSB has the technician hook up to pin 16 on connector 1F at the main body ECU (MBECU). That is what I did.

Steps for accessing the MBECU:

1. Slide front left seat back
2. Disconnect battery if it isn’t still disconnected from Part I
3. Remove the floor mat (twist the little lock 90 degrees and lift up)
4. Remove the front left door sill trim piece (pull up)
5. Remove left kick panel (remove the thumb nut securing the panel, then pry the panel towards the console)
6. Remove the 3 10mm head bolts holding steering column trim to dash frame
7. Gently pull on the trim panel around the perimeter, freeing the clips
8. Unplug all the switch connectors (TRAC, clutch start cancel, cargo, etc)
9. Drop the panel to the floor. You will see the MBECU.

Connector 1F is the one circled in green in the photo below. That is the one I worked on.



Use a small flat-blade screwdriver, push downward on the tab at the top of the connector. While pressing down, grab the black connector lock and rotate it outwards. This will remove the connector from the MBECU.



Undo the electrical tape and free up 4-5” of wire. Find the gray wire coming from cavity 16. This is the circuit we want. Splice into it how you prefer. Do a good job because these are important to the operation of your truck. Hack jobs don’t belong in automotive wiring. I use very strong non-insulated barrel butt connectors with a Thomas and Betts crimper that crimps them so tightly they can’t possibly pull apart. In this case I used a step-down butt splice because it has a small 20-24AWG end for the small stock wire, and then a larger 18AWG end for my added wire and the other side of the cut stock wire. See in photo above.



Slide on heat shrink before crimping both sides. Crimp both sides. Heat the heat shrink.



Wrap back up the stock electrical tape and then add some of your own harness tape (Tesa or similar) to secure it. Plug back in, reassemble dash. Part II done.

I met this wire up with the wire from part I, taped the two together and ran them out the left firewall grommet and ran them to my relay.

Part III: Fan Installation:

Part 3.1: Fan Assembly

Like I mentioned earlier, @Jeff Lange helped me by pointing out the parts to build the fan myself. The factory fan assembly is very expensive and I saved around $300 building it myself.

Using the part numbers mentioned earlier, you end up with this:



Start to assemble.



Set the fan motor down, blade side up, wire side down. Set shroud face down on top of motor.



Install the 3 larger (90099-04119) screws to secure the motor to shroud. Snug them down with a Philips screwdriver.



Set the blade down on the motor. It can only go one way due to the shape of the fan blade hub. Install 3 smaller (90099-04117) screws and snug with a Philips screwdriver.



Flip the assembly over. Install the wiring connector clip into the hole circled in red. Slide the motor’s connector onto the clip. Clip the wires into the two grips shown on the fan shroud.



Fan assembly complete.

Part 3.2: Fan Mounting

Remove the grille:

1. Remove the 2 10mm head bolts
2. Remove the 2 quick fasteners
3. If applicable, unplug the TSS harness and undo the harness clip to free harness from grille
4. Pull grille away from truck, set aside

Slip the fan shroud’s feet onto the core support. Grab your two purchased bolts (90119-A0078) and thread them into the core support. Snug with a ratchet or wrench. Don’t pinch the wires on the core support center piece.


Part 3.3: Assembling Fan Connector and Extending Wiring



I don’t have much photos for this, but take your Connector F (90980-11237) and your two 82998-12480 wires and insert them into the backside of Connector F. The terminals will click into place. Push in the white wedge lock on Connector F to lock the wires in.



Plug in the connector and extend your wiring as needed. Blue is positive, black is ground. I used similar non-insulated butt splices (with my own heat shrink) and 12AWG primary wire from O’Reilly in proper colors.



I wrapped the two wires into Tesa tape and then shoved the bundle into heat rated split loom. I zip tied my harness to an existing fog light harness and ran to my relay location.

Part 3.4: Showing some of my wiring



I used my custom fuse panel for this so my work doesn’t really apply. I had one unused relay left, so it made sense. Whatever you do, use power for the relay (30 terminal) straight from the battery. And USE A FUSE.

Your relay should be hooked up as follows:

86 - Ignition wire from Part II
85 - Ground (control) from Part I
30 - Properly fused battery power
87 - blue wire to fan
Fan ground - go to fender bolt or battery (-)


Noise

It’s honestly a lot quieter than I expected it to be. Based on noise, you can’t tell if it’s running unless you’re right in front of the grille. It would be kind of neat to install a small LED indicator in the dash wired up to the fan to see when it’s on in different conditions.

Here’s a video showing it cycling to get an idea of the noise.




Final Thoughts - Was it all worth it?!

I think it was. I can’t give any concrete evidence for how well it works, such as dash temps, mainly because I have no control of when the fan turns on, and the temps outside vary too much. Lots of time (90° and below), the fan doesn’t seem to come on except randomly sometimes. When it’s hot out (100°+), it’s on most of the time.

I certainly feel like things work better. It seems like the air gets cooler more quickly at startup and stays that way at idle. I mean, it’s a factory part on the Mexico trucks, so surely it HAS to be making some difference or else Toyota wouldn’t give any trucks the fan nor perform the TSB.

I did this for two reasons, one being the boosted A/C performance, and two being I just like to install improvement stock-like stuff on my vehicles. I like to be unique and have the best setup I can have as long as there are no downsides. For $400, I’m happy with my install. And while the install seems lengthy, it’s really not that bad. There is just no way to make the write up be short and still have all the pertinent info.

 

FML. That is one of the nastiest TSBs that I have seen. I cannot believe that you attempted / succeeded with it.

There is a similar but different issue on my old bike. If the rad temp got to about 200F, it was hard to keep it from gaining more if going along slowly. So, a lot of us tossed in a manual fan switch. We'd just flick it on at about 190F or so. The temps would remain stable. The factory values was 220F or higher, which was hard to keep it away from 240F boil over.

Anyway, I like the idea of the condenser fan. But, my simpleton self would go with a manual switch. Just funny considering the drastic differences in approaches. Haha!




Killer work and writeup!

 

My A/C sucks unless I'm at freeway speeds. 2016 built in Mexico.

 

@BLtheP get the award for the best post of the year!

 

Factory location for CDS Fan Relay, with terminals and some skill, one could install OEM.

 

great write up and great work from the team!

 

Unfortunately doesn’t matter where it’s built, it’s where it’s destined to that determines how it’s built. Meaning you don’t have the extra fan if it’s a US destined truck.

That said, sounds like you might have another problem because mine has always worked fine at below freeway speeds.

 

Ya know, the TSB appears pretty daunting and like a hack job, but it's actually not that bad. The worst part was on the early versions of the TSB, they were giving an improper fit fan and instructing the techs to hack off part of the shroud, which was weird and definitely makes people second guess the process. No idea why they would do that when the proper fit Mexico fan always existed.

The wiring seems scary, but really it is just a premade harness (in the TSB) that hooks up to two wires in the cab. The TSB makes it seem like more work than it is, because the control wire can be 1 of 4 ways:

• manual AC connector A14 with no wire in place (insert pin with wire)
• manual AC connector A14 with wire in place (cut and splice)
• auto AC connector A35 with no wire in place (insert pin with wire)
• auto AC connector A35 with wire in place (cut and splice)

The reason for this is because some instrument panel harnesses have the wires in place, and some don't. The ones that have it in place you can just splice to more easily than you can remove the wire and repin the connector with the pin insertion technique, so they include the instructions for both. Same for the wire at the MBECU. They have to include the steps for either method, which makes it seem like there is a whole bunch of splicing and wire running in the TSB, but really in the cab it is just a simple two wires that trigger a relay that need to be hooked up.

Other than that it's just power and ground on 12 gauge wires like any other accessory. It does seem daunting based on the TSB though.

Interesting on the motorcycle, makes sense to just turn the fan on there.

 

I have seen a lot of wrong stuff in the TSBs, esp instructions to do much more work that is necesary. The B Team is definitely writing those up.


Those Cliff's Notes are not bad. Modern refrigerants do suck in town and for cooling down a hot car at startup. I miss freon.

 

Could you essentially mount a fan after fabricating a quick bracket for it, then just wire it to a switch/ switch controller and turn it on as needed?

 

You can mount whatever you want and control it however you want. I personally wouldn’t want to have to remember to turn it on all the time though. How am I to know the best time to turn it on? If it’s for AC performance, it seems letting the AC brain decide is the best move really because it’ll turn it on when it’s beneficial.

 

Right, I'm just thinking from an easier perspective here. In theory, you could do what I mentioned. The only time I've ever felt like I need a fan would be sitting still for long periods of times, which I could just kick it on as I feel it's needed.

I love the idea and props to you for doing it, I myself just wouldn't go through the hassle of ripping apart the dash to get it wired in lol.

 

I get it. Yes, you could absolutely do that if you feel like controlling it. I would suggest at bare minimum, your switch controls the ground side of the relay and your power to the relay coil be an ignition source so that you can’t accidentally leave the fan on after the truck is off.

Really though, it might just be my tenacity, but other than buying overpriced wiring terminals from Toyota, the work behind the dash wasn’t that much. The work to add the wire to the AC control plug is the same work you do to install the 2lo kit. Tons have done that one. The other portion is just for ignition power, which could be found elsewhere although grabbing power there was very simple and I was done in less than an hour there for sure.

 

Don't buy the Toyota repair terminal with crimped wire. Get the terminal and crimp it yourself.

 

I like the Toyota version since it didn’t require buying a crimper and I was able to buy locally same day. If not in a rush and either have the crimper already or don’t mind buying it, then self assembling the terminals is probably a better deal. When it came down to it, I would rather butt splice than crimp stock terminals. It helps that use good splices and not generic junk from the hardware store.

 

These work great and aren't too expensive:

 

Very ambitious and well documented project OP! I admire your patience and tenacity. I considered powering my fan through a relay that would automatically turn on whenever the AC compressor was on, but just did the quick but clean DIY attach it to an auxiliary switch position on my accessory switch panel. The AC works really well now, even when parked with 110+ degree temps outside. I may go with both the relay and the switch as an override, because it would be helpful for using it when towing without the AC being on, or when 4WD crawling…

 

Any link to the original TSB mentioned in the first and some subsequent posts? TIA

 

I have noticed this issue as well. On those very hot days here in Canada, the A/C can be tepid while idling. Once you get moving it works good. Mentioned this to dealer last year and they said no fault found. Not surprised. The Car Care Nut even covers this issue. He called out Toyota for cutting this fan out. He said it should be standard in all Tacoma's. Ultimatly, I don't know if I really wanted the dealership ripping things apart in the end. We don't get that many days I feel the A/C struggling to keep up at idle. Thanks @BLtheP for this comprehensive installation guide. Beyond my skill set and patience tho.