[email protected] 0 Posted December 30, 2021 I have a 1987 Honda trx350D. The fan control unit malfunctioned, discontinued and the only NOS is 400.00. The 1995-2006 TRX400fw has the same schematic as the 1987. The only difference I can see is the 87 has a 6 individual wire pigtail and the 95-06 uses 2 plug in connectors with a total of 6 wires. I want to modify my 87 atv harness from 6 individual wire pigtail to the 2 plug style. I can figure out the 2 wire connector is the thermal sensor, the 4 wire plug is another story, which wire goes to which terminal? Any Ideas? Share this post Link to post Share on other sites
Fishfiles 20,145 Posted December 30, 2021 Hi , here is a used fan control module , to fit a 1986-1989 TRX350D for $123 on e-bay with free shipping ---- i think your asking for trouble modifing the wiring harness , that would be a last resort https://www.ebay.com/itm/362868015158?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A1SAa2XchXTTGlbbdDzTqi4Q97&norover=1&mkevt=1&mkrid=711-213727-13078-0&mkcid=2&itemid=362868015158&targetid=4581046488761455&device=c&mktype=&googleloc=&poi=&campaignid=418640322&mkgroupid=1239149842233245&rlsatarget=pla-4581046488761455&abcId=9300602&merchantid=51291&msclkid=171cd8536b3c1dd8ab4eb99ef89681d7 2 Share this post Link to post Share on other sites
shadetree 5,864 Posted December 30, 2021 i'm all for oem, never would i '' jerry rig '' wires on my toys. if funds is an issue ?, then just install a fan bypass switch, be done with it. 3 Share this post Link to post Share on other sites
Fishfiles 20,145 Posted December 30, 2021 By-Pass like Shade says is a good way to go ------- and you can take the by pass to the next level with a Summit fan controller , on my 95 300 I have two fans and the oil coolers relocated , this little Gizmo controls which temp the two fans kick on indepently , cost was $75 two years ago , made by David White out of Australia , sold by Summit Racing , and you don't have to cut into the existing harness ---- Retro makes a very nice fan controller from scratch and Goober is his apprentice , I have one on my 450 , there is a nice thread on it here on the site 1 Share this post Link to post Share on other sites
[email protected] 0 Posted December 30, 2021 I agree, OEM is the way to go and I am going to use an OEM fan control unit. Honda discontinued it and I don't trust used electronics. I'm trying to use what OEM still makes. Here are an 87 trx 350D and a 95-03 trx 400FW schematics, what is the difference, except the connectors? Share this post Link to post Share on other sites
[email protected] 0 Posted December 30, 2021 If I could switch to the newer connectors then I could use this FCM. Honda Fourtrax Foreman 350 D 87 Fan Control Unit 38710-ha7-671 31435 Good Usable Condition. Honda Fourtrax Foreman 350 D 87 Fan control unit 38710-HA7-671 31435 123.99 Product Details Manufacturer Part Number 38710-HA7-671 Shipping Our mission ... Honda View product details $123.99$123.99.Used +$6.82 est. tax eBay - powersportsnation Free delivery by Tue, Jan 11 Share this post Link to post Share on other sites
Goober 1,555 Posted January 1, 2022 On 12/30/2021 at 4:39 PM, [email protected] said: If I could switch to the newer connectors then I could use this FCM. Honda Fourtrax Foreman 350 D 87 Fan Control Unit 38710-ha7-671 31435 Good Usable Condition. Honda Fourtrax Foreman 350 D 87 Fan control unit 38710-HA7-671 31435 123.99 Product Details Manufacturer Part Number 38710-HA7-671 Shipping Our mission ... Honda View product details $123.99$123.99.Used +$6.82 est. tax eBay - powersportsnation Free delivery by Tue, Jan 11 This is not a fan control unit; this is a fuel cutoff relay. Share this post Link to post Share on other sites
350DD 1 Posted January 2, 2022 Sorry about the repeat of this post but I had to change my email and display name. I have a 1987 Honda trx350D. The fan control unit malfunctioned, discontinued and the only NOS is 400.00. The 1995-2006 TRX400fw has the same schematic as the 1987. The only difference I can see is the 87 has a 6 individual wire pigtail and the 95-06 uses 2 plug in connectors with a total of 6 wires. I want to modify my 87 atv harness from 6 individual wire pigtail to the 2 plug style. I can figure out the 2 wire connector is the thermal sensor, the 4 wire plug is another story, which wire goes to which terminal? Any Ideas? I agree, OEM is the way to go and I am going to use an OEM fan control unit. Honda discontinued it and I don't trust used electronics. I'm trying to use what OEM still makes. Here are a 95-03 trx 400FW and an 87 trx 350D schematics, what is the difference, except the connectors? Share this post Link to post Share on other sites
Goober 1,555 Posted January 2, 2022 (edited) Rocky Mountain atv shows all 86-89 TRX350A and D FCU are the same pn: 38710-HA7-671 supersede 38710-HA7-651 Here’s one from Power Sports Nation. 30-day warranty. The listing appears to have the wrong part number 36100-HA7-671 is the fuel cut relay Update Hay this listing seems wrong why is this coming up on my FCU search? https://www.ebay.com/itm/Honda-Foreman-TRX-350-D-88-Fuel-relay-36100-HA7-671-30800-/363503984030?mkcid=16&mkevt=1&_trksid=p2349624.m2548.l6249&mkrid=711-127632-2357-0 Edited January 2, 2022 by Goober Share this post Link to post Share on other sites
bcsman 1,382 Posted January 4, 2022 OK 350DD, took the front of my 450ES apart and took this pic of the fan control. You should be able to see what wires go where on the 2 plugs. Share this post Link to post Share on other sites
Fishfiles 20,145 Posted January 5, 2022 7 minutes ago, bcsman said: OK 350DD, took the front of my 450ES apart and took this pic of the fan control. You should be able to see what wires go where on the 2 plugs. BCS , Looks like the light blue wire to your temp sensor has been repaired with spade connectors Share this post Link to post Share on other sites
bcsman 1,382 Posted January 5, 2022 Yes fish when I installed a fan switch it was part of my mod...... Share this post Link to post Share on other sites
350DD 1 Posted January 5, 2022 Thank you very much! I'll post the results. 1 Share this post Link to post Share on other sites
bcsman 1,382 Posted January 5, 2022 12 hours ago, 350DD said: Thank you very much! I'll post the results. Hope it helps, thankfully had the front end apart a few times and didn't take as long as first time. Just have to remember where all the fasteners and bolts go....lol Share this post Link to post Share on other sites