Electric fan wiring

[Dream240]

I been searching on here for some answers but nothing yet. So here goes.

I'm still working on my front end restore, the accident destroyed my electrical fan and clutch fan. I bought an aluminum radiator and 2 10" fans.

My problem is that I've got 2 wires from each fan, and 4 wires on the old OEM fan. And based on what I've found on Zilvia, no one has just taken the new fans and spliced them straight up to the engine harness with the old fans wiring.

Why is this? I'm reading that everyone gets relays and wires up some 30A fuses to make them work. I am assuming this is because the OEM relay is actually in the electric fan housing.....right?

Unfortunately I'm running out of insurance money and I just want to make sure I get this right. So would this be an okay relay to buy? Would I need two of them, one for each fan?

Amazon.com: Flex-a-lite 31147 Adjustable Temperature Control Unit: Automotive (http://www.amazon.com/dp/B00029J3ZW/ref=asc_df_B00029J3ZW1014165?smid=ATVPDKIKX0DER&tag=googlecom09c9-20&linkCode=asn&creative=380341&creativeASIN=B00029J3ZW)

Any info would be helpful.

thanks guys.

[midnight_rex]

that is ok but the sensor will need to be routed in the cooling system which i dont think is a good design at all.

Amazon.com: Hayden, Inc. 3651 Cooling Fan Control: Automotive (http://www.amazon.com/dp/B000C39C72/ref=asc_df_B000C39C721014165?smid=ATVPDKIKX0DER&tag=googlecom09c9-20&linkCode=asn&creative=380341&creativeASIN=B000C39C72)

hayden makes some good and simple controllers. im using one just like this one. this is prolly a revised product from the one i got. it comes with its own temp sensor which u can tap anywhere from a cooling component and pugs/unplugs when u need it.

[projectRDM]

S14 I assume?

There's four wires because the OE electric fan is a two speed unit. Each circuit is fused and has a relay. Low speed comes on at 203 degrees, high speed at 212 degrees or when the A/C is engaged.

[Dream240]

S14 I assume?

There's four wires because the OE electric fan is a two speed unit. Each circuit is fused and has a relay. Low speed comes on at 203 degrees, high speed at 212 degrees or when the A/C is engaged.

Yeah, it's an S14.

Okay I got that, but where are the relay units? Are they in the fan motor housing or further back past the harness connector on the engine bay side? Just trying to see if my idea will work to save me some cash.

Thanks Russ.

[fliprayzin240sx]

S14 I assume?

There's four wires because the OE electric fan is a two speed unit. Each circuit is fused and has a relay. Low speed comes on at 203 degrees, high speed at 212 degrees or when the A/C is engaged.

So hypothetically, you can wire 2 fans into it and have one on at 203 and the other one come on at 212 or with the AC?

[projectRDM]

Yeah, it's an S14.

Okay I got that, but where are the relay units? Are they in the fan motor housing or further back past the harness connector on the engine bay side? Just trying to see if my idea will work to save me some cash.

Thanks Russ.

The relays are both in the underhood fusebox, marked fan relay lo and hi I believe. I've never seen a relay in a wiring harness.

[Dream240]

The relays are both in the underhood fusebox, marked fan relay lo and hi I believe. I've never seen a relay in a wiring harness.

Okay, sweet. Thanks for that info.

I'm just going to wire the fans up, one to come on at low speed and one at high speed based on the 4 wires. Since I'm not replacing the clutch fan and I'm running a new aluminum radiator and thermo, I should be good for temps.

Thanks guys.

[westly7]

The relays are both in the underhood fusebox, marked fan relay lo and hi I believe. I've never seen a relay in a wiring harness.
im trying to make my e-fans work and i did try to hook on either one lo (brown wire) and hi (white with red stripe in it) under the fuse box but they still not working.have any clue?

[Sileighty_85]

im trying to make my e-fans work and i did try to hook on either one lo (brown wire) and hi (white with red stripe in it) under the fuse box but they still not working.have any clue?

Did you let the engine warm up to the Temps Posted previously?

They wont kick on until the Temp is reached

[westly7]

i did try let my car on for while till temp almost reach hot position about 3/4 more and nothing happened

[chituntang]

Use a volt meter to see if any current flows though the wires.

And the E fan is only activated when the A/C is on. So under normal driving condition, it/they will not come on.

[Dream240]

Use a volt meter to see if any current flows though the wires.

And the E fan is only activated when the A/C is on. So under normal driving condition, it/they will not come on.


Not necessarily true. The high fan will kick in automatically when the AC is turned on yes, but it will also come on when the engine temp goes above 218 IIRC. The low fan temp is 209 IIRC, or somewhere around there.

[westly7]

Not necessarily true. The high fan will kick in automatically when the AC is turned on yes, but it will also come on when the engine temp goes above 218 IIRC. The low fan temp is 209 IIRC, or somewhere around there.
im pretty sure that my temp was more than 208 or above bc it almost reach top and nothing happened to the fans. even i checked with test light that there were no power coming out (both HI and LOW) and i did turn on the a/c and off still

[chituntang]

Not necessarily true. The high fan will kick in automatically when the AC is turned on yes, but it will also come on when the engine temp goes above 218 IIRC. The low fan temp is 209 IIRC, or somewhere around there.

I have on hand 95 and 96 240sx FSM and they both told me that the fan are controlled by the thermo control amp, and it is somehow connected to the push control unit. And the FSM also does not show any relationship between the thermo control amp and the coolant temperature.

To the OP: Humm..... Have you try the fans by themselves yet?

[s14canyoncity]

i assume some of the chat in here, referring to this write up:

Electric Fans in a s14 (http://www.240sx.org/links/installs/efans/index.html)

I followed this write up the first time and had no luck myself. Ended up wiring my fans in parallel and running a relay and using one of the ACC fuse to trigger the fan. The only thing that sucks is that the fan is on when key is turned to ACC. Other than that the electric fans kick ass.

and yes i did sit and wait till the engine warmed up ....

[westly7]

i assume some of the chat in here, referring to this write up:

Electric Fans in a s14 (http://www.240sx.org/links/installs/efans/index.html)

I followed this write up the first time and had no luck myself. Ended up wiring my fans in parallel and running a relay and using one of the ACC fuse to trigger the fan. The only thing that sucks is that the fan is on when key is turned to ACC. Other than that the electric fans kick ass.

and yes i did sit and wait till the engine warmed up ....
i did this way too and had no luck too :doh:.that blue green wire in my fuse box doesnt have power,even i tried to find power with test light on every wire on rad fan hi and lo relay.so im doing individual relay on every fan that hooks to acc instead

[Dream240]

I have on hand 95 and 96 240sx FSM and they both told me that the fan are controlled by the thermo control amp, and it is somehow connected to the push control unit. And the FSM also does not show any relationship between the thermo control amp and the coolant temperature.

To the OP: Humm..... Have you try the fans by themselves yet?

Okay, well from personal experience, all 4 of my S14s have had the OEM electrical fan setup which would kick on when the temp rose too high. And my current 95 S14, I replaced the OEM fan with 2 10" fans and simply spliced the wires for each fan to the 4 existing wires that went to the OE fan from the engine harness. Bam, fan #1 kicks on, then when temp gets higher or A/C is turned on, BAM, fan #2 kicks on. It's not rocket science.

To OP if your fans are not kicking on, check the relays first. Prolly bad relays.

[DALAZ_68]

so...the relays tell the fans at what temp to kick in?


if thats the case, could you buy relays that kick the fans on at lower temps...

in other words, replace your stock 203*, 212* temp relays with some that kick in sooner...?

just wondering...s14 are still ew to me...

pretty much remove stock relays and put them in the fuse box for stock looks...?

[ADiamond240sx]

Ummm ... Check EC 205 in the FSM for relay info in regards to the fan control. EC206 has the wire colors and descriptions. I would use a temp sensor to control one of the fans.... here is a brief description of how I wired up my dual electric fans:

I wired the main one up to a thermal sensor relay with an override to the second relay triggered by the ECU (Fan HI relay) and the second fan hooked up to the fan LOW relay. This way the car cools properly and the AC fan comes on when it should. Furthermore, if the thermal sensor fails the second relay will override it and prevent the car from overheating. The thermal sensor is hooked up to constant power which allows the fan to cool the car down for a few minutes after the car is shut off. It works great.

Cliffnotes

Fan one: Thermal sensor with relay that has override which is connected to second stock relay (fan HI).

Fan two: Hooked up to first stock relay (fan LOW).

[s14canyoncity]

just wondering...s14 are still ew to me...



Hater....lol when you gonna sell me your DD? :rofl:

[projectRDM]

so...the relays tell the fans at what temp to kick in?


if thats the case, could you buy relays that kick the fans on at lower temps...

in other words, replace your stock 203*, 212* temp relays with some that kick in sooner...?

just wondering...s14 are still ew to me...

pretty much remove stock relays and put them in the fuse box for stock looks...?

No. The relays are triggered by the ECU. There's no way to trigger them earlier unless you buy a fan controller of some sort, like a Pivot model, to trigger them at preset lower temps. Relays are not thermo controlled.

[projectRDM]

I have on hand 95 and 96 240sx FSM and they both told me that the fan are controlled by the thermo control amp, and it is somehow connected to the push control unit. And the FSM also does not show any relationship between the thermo control amp and the coolant temperature.

To the OP: Humm..... Have you try the fans by themselves yet?

That is incorrect. The Kouki models don't even have a thermo control amp. The cooling fans are controlled through relays via the ECU, by both the CTS and A/C on signals. When the A/C is engaged the ECU automatically triggers both relays to turn the fan on high speed.