TSB-0063-18 A/C issue

What dealership?

 

It was my mistake, there appears to be a relay, not a thermistor. Sorry! Anyhow, what is this stupid thing doing putting another relay box on the fender wall, and who wires in a basic electric 12v fan like that!!?? I still cant believe the amount of work it calls for just to put a blower fan up front. Im having second thoughts about doing it for the idiocies of this TSB, its a Rube Goldberg fix with too much that can go wrong, especially with someone cutting and tieing into those harnesses.

Besides, Im using some of the areas they want to use for the parts and Im not relocating my battery switches. Just the Toyota fan they use costs over $450 retail, I’ll just get a Bosch aftermarket blower for a lot less and DIY it.

Ok, rant over. Where’s my coffee?

 

Keep ranting.
Same feelings you are having. Figured might as well have them do it while still in warranty. But a bit worried about them digging into wiring especially at the ECU near where I already have 2wheel low mod, and right hand passenger touch and front camera, and dash cam.

Did you notice they hack off one of legs of the fan mount. Rube goldberg may be giving them too much credit.


Just wish had better schematic of the mod to understand how they did switching...

 

I really don’t get the switching. Why not just enable it when the compressor clutch is energized?

 

There is no way I’m letting them do this to my truck. What a Mickey Mouse fix. I would expect something like this from a repair shop in Tijuana.

 

Ok, so Im doing it myself. Besides, having the ability to manually turn on the fans when wheeling slowly or towing my camper trailer in summer and up steep grades in the heat will help the engine keep cooler too, with or without the AC on. So I bought these 12 inch fans to try out:

$40 MOSTPLUS Black Universal Electric Radiator Slim Fan Push/Pull 12V + Mounting Kit (12") Set of 2

https://www.amazon.com/MOSTPLUS-Universal-Electric-Radiator-Mounting/dp/B077YD2Z9Q

 

Please document your progress so others can follow along.

 

Along wirh my trials and errors!

 

Folsom Lake Toyota. CA

 

Did some research on the ECU wiring that the TSB ties into. By looking at the 3rd gen schematic, I noticed the "mexico" model trucks already appears to come with a condenser fan. The ECU already is outputting a command to power a fan on-and off, that isn't installed on US trucks. So they were just copying the mexico wiring, and that likely is why the stupid TSB wiring that goes in and picks up the existing ECU pins like it does.

(so why are they hacking up a fan, if the mexico already has a fan, that I assume doesnt need hacking...)

So the TSB pulls from one pin for 12V when ignition switch is on.
The TSB pulls another pin for the relay control ground when fan is commanded on (by the ECU).
The TSB attaches 12v relay power from battery, and grounds to body.

 

Hmmm, interesting. Mine is a Mexican Taco though, and doesnt have a electric condenser fan. Thanks for the schematic- some options to ponder. I do want a manual overide though, so I can turn them on when doing heavy hauling or 4-wheeling and the engine temp exceeds 180 in summer.

 

This TSB and fix is a curiosity. I have 18 that cools just fine at idle in 95-100 degree heat and humidity. My truck was built in TX so it does not have a electric fan. Why would Toyota 're-engineer' the system to add that fan? They are basically saying they have no f'ing idea why some trucks are not cooling and this is their 'fix'. I would assume that any 18 from TX should/would perform like mine. The only thing I can think of is there are part(s) that are different on some trucks. Otherwise, Toyota should be replacing defective parts. IDK, but it's an interesting 'solution'. Curious if this is being reported on MT and AT trucks.

 

Its not the fabrication country. Its the target destination country I think.

 

So how does the ecu know when to turn on the supplemental fan? Outside air temp? I can’t imagine you’d want the fan running when your cruising along at 70mph...

 

Haven't been able to figure it out. The ECU decides, but I haven't seen anything in the repair manual to tell us about that decision.

 

So we need someone who’s had this TSB done to report when the fan comes on. Also, it would seem like the fan would actually reduce airflow under most conditions as it sits right in front of the condenser. Right?

 

Yeah, there would be some restriction. Good point about speed- maybe its determined by temp, gear and/or speed.

 

I’m experiencing the same issue with mine too

 

This is the start of the info on the problem. https://www.tacomaworld.com/threads/3rd-gen-tacoma-a-c-noise.550627/

 

Just need someone to hook a meter to the correct pin on the ecu. Next time I have techstream plugged in I will try to see if there is a fan status in techstream... if it is ECU controlled I assume it will have a status in techstream. (Probably wont be hooking up next until next time I install ovtune update 1.05, whenever that happens)