Author Topic: help finding replacement for this BLDC fan controller  (Read 731 times)

0 Members and 1 Guest are viewing this topic.

Offline administr4torTopic starter

  • Contributor
  • Posts: 39
  • Country: ca
help finding replacement for this BLDC fan controller
« on: May 01, 2026, 04:02:41 pm »




[/img]




its for a Radiator Fan for automobile car
OEM part is out of stock

any way I can find a replacement part for it somewhere?

please help

THanks
« Last Edit: May 01, 2026, 04:56:12 pm by administr4tor »
 

Offline Randy222

  • Super Contributor
  • ***
  • Posts: 1382
  • Country: ca
Re: help finding replacement for this BLDC fan controller
« Reply #1 on: May 01, 2026, 05:39:35 pm »
Inside that box is likely just a FET with a pull-down resistor. It may also have a zener or diode to squash flyback.

The FET gate may also have a small resistor on it, but the device looks automotive, and many times the ECU control line has the resistor in the ECU.

The ENABLE line can just be an SSR, so it provides power to the ckt, but the FET swicthes the motor on/off to the beat of BLUE PWM.

The wire-gram on unit shows 6 connections, but the 3 connectors have 8 ??

Making the device should be very easy.
 

Offline Uunoctium

  • Frequent Contributor
  • **
  • Posts: 424
  • Country: de
Re: help finding replacement for this BLDC fan controller
« Reply #2 on: May 01, 2026, 05:45:01 pm »
Comex is still alive and produces three different types of fan controllers. You may write them an email and ask, if one of the types is suitable as an replacement for your damaged one. (probably only with some modifications eg replacing the NTC with an fixed resistor).

https://www.comex-europe.com/cms/en871-electronic-speed-control.asp
 

Offline thm_w

  • Super Contributor
  • ***
  • Posts: 9490
  • Country: ca
  • Non-expert
Profile -> Modify profile -> Look and Layout ->  Don't show users' signatures
 

Offline Randy222

  • Super Contributor
  • ***
  • Posts: 1382
  • Country: ca
Re: help finding replacement for this BLDC fan controller
« Reply #4 on: May 03, 2026, 12:56:59 am »
That one from CA site, $327(CAN) !!
Yikes, can build probably a dozen of them from discrete parts for that price.

Buying a cots is always easier, but I do evaluate DIY.
 
The following users thanked this post: administr4tor

Offline amyk

  • Super Contributor
  • ***
  • Posts: 9086
Re: help finding replacement for this BLDC fan controller
« Reply #5 on: May 03, 2026, 02:05:57 am »
My guess is the inside has not much more than a relay and two FETs, and maybe a few passives.

"Don't turn it on, take it apart!" :D
 

Offline administr4torTopic starter

  • Contributor
  • Posts: 39
  • Country: ca
Re: help finding replacement for this BLDC fan controller
« Reply #6 on: May 03, 2026, 08:43:14 pm »
yeah, thats one of the reason I am trying to find alternate, why pay $350 when you get it cheaper elsewhere?


I found this, do you think it will work? the Audi one is rated for 60A, while Triumph one is rated 20A (?) atleast thats the fuse I see in Triumph diagram.


https://www.amazon.com/-/fr/No-8E0959501AG-8E0959501AB-8E0959501K-ventilateur-refroidissement/dp/B0CHS8X9QW



below is PIN out and OEM Audi Electrical diagram for the Audi cooling fan PWM module






if you think it will work, what pins replace what pins , i need conversion of pins between amazon and triumph module, based on information above.

Thanks for helping me out


My guess is the inside has not much more than a relay and two FETs, and maybe a few passives.

"Don't turn it on, take it apart!" :D
That one from CA site, $327(CAN) !!
Yikes, can build probably a dozen of them from discrete parts for that price.

Buying a cots is always easier, but I do evaluate DIY.
ebay: https://www.ebay.ca/itm/314431717115
auto wrecker

Is it the same as this one? https://fortnine.ca/en/triumph-fan-pwm-controller-t2507700
Comex is still alive and produces three different types of fan controllers. You may write them an email and ask, if one of the types is suitable as an replacement for your damaged one. (probably only with some modifications eg replacing the NTC with an fixed resistor).

https://www.comex-europe.com/cms/en871-electronic-speed-control.asp
« Last Edit: May 03, 2026, 09:08:59 pm by administr4tor »
 

Offline administr4torTopic starter

  • Contributor
  • Posts: 39
  • Country: ca
Re: help finding replacement for this BLDC fan controller
« Reply #7 on: May 11, 2026, 08:06:30 pm »
:bump:
 

Offline Randy222

  • Super Contributor
  • ***
  • Posts: 1382
  • Country: ca
Re: help finding replacement for this BLDC fan controller
« Reply #8 on: May 12, 2026, 05:55:27 am »


I found this, do you think it will work? the Audi one is rated for 60A, while Triumph one is rated 20A (?) atleast thats the fuse I see in Triumph diagram.


https://www.amazon.com/-/fr/No-8E0959501AG-8E0959501AB-8E0959501K-ventilateur-refroidissement/dp/B0CHS8X9QW
Is the plug a direct fit? I can say with 100% certainty, it may or may not work.

The original side label only shows one (M) motor, so probably the two "white" connectors for fans are wired in parallel. It is very likely to be a current sink controller. Two nFET's in series, yellow gates one, the blue PWM turns on/off the 2nd FET. Yellow (ignition) so that the fans cant stay running after the key has gone to off.

Probably just easier to build a replacement.
IRF low Rds very high amps, decent 40v, use diode to quench flyback
IRFB7434PBF

1k pull-down on gates.

Plenty of helpers around on this site to drum up schematic as needed.

 
The following users thanked this post: administr4tor

Offline Smokey

  • Super Contributor
  • ***
  • Posts: 3703
  • Country: us
  • Not An Expert
Re: help finding replacement for this BLDC fan controller
« Reply #9 on: May 12, 2026, 07:40:42 am »
 
The following users thanked this post: administr4tor

Offline administr4torTopic starter

  • Contributor
  • Posts: 39
  • Country: ca
Re: help finding replacement for this BLDC fan controller
« Reply #10 on: May 13, 2026, 11:16:29 pm »
how do I make my own?
 

Offline Randy222

  • Super Contributor
  • ***
  • Posts: 1382
  • Country: ca
Re: help finding replacement for this BLDC fan controller
« Reply #11 on: May 13, 2026, 11:21:43 pm »
how do I make my own?
Start a thread in the Projects forum.
"Need Schematic For DIY Controller"

It's very simple to make.
 

Offline aeg

  • Frequent Contributor
  • **
  • Posts: 351
  • Country: us
Re: help finding replacement for this BLDC fan controller
« Reply #12 on: May 14, 2026, 03:05:18 am »
I think the mechanical and thermal aspects are the hard part...
 

Offline Randy222

  • Super Contributor
  • ***
  • Posts: 1382
  • Country: ca
Re: help finding replacement for this BLDC fan controller
« Reply #13 on: May 14, 2026, 03:28:23 am »
I think the mechanical and thermal aspects are the hard part...
What mechanical aspects?

Some discrete components potted. Should be no issue for automotive use.

Something like this she-matic. ;)



« Last Edit: May 14, 2026, 03:58:42 am by Randy222 »
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf