R00567

Background: I have a 2007 AP2 (or the newer 2006+ ap2).
1) Recently i replaced the stock radiator with a Koyo unit. (evasive sent me the 2006+ s2000 fan switch adapter for the koyo radiator)
2) I also installed a mishimoto shroud.
3) I took the liberty to ditch the mishi fans and replace them with Spal Fans (i have 2 12'n spal fans where the old Mishi fans were mounted).
4) Mishi fans had OEM plugs which i spliced onto the Spal fans because the Spal fans had different plugs (so i am using OEM / stock wiring configuration).
5) replaced the cooling fan fuse in the engine bay fuse box from a 20 --> 30A.
6) did the same for the AC condenser fan in the engine bay fuse box (20 --> 30A).
7) Relays have been checked, and i have a OEM thermostat.
8) i have a HOT heater, and COLD AC.
9) the car doesn't have temp problems unless its a hot day and the AC is on (after i shut the AC off the single Spal does a good job cooling everything back to happy levels).

Problem:
1) i can only get 1 of my fans to come on for both cooling and the AC. (the fan that turns on is the driver side, passenger side one does NOT power up).
2) to my understanding both fans are supposed to turn on, at least when the AC is switched on and the key is in the ON position before the car is started.
3) I do not know the cause for my second cooling fan to not power up. (i'm assuming the AC fan is the one on the passenger side of the car - RIGHT side).

Trouble Shooting:
1) used a 12V source to power up both fans at the plugs (both fans came on)
2) tried jumping the AC condenser fan relay at the engine bay fuse box location (and the RIGHT SIDE fan powered right up)
3) my AC system was fully vacuumed out and replaced / topped off with freeon (so my AC system is charged)

Questions:
1) do i have a bad fan switch? (then why would my fan come on when the engine needs to be cooled down?)
2) is there another thermal switch on the 2006+ ap2's i might have bad (the intake manifold one)?
3) is there a thermal switch that controls the AC condenser fan to come on?
4) should i check the relays again?
5) should i check the fuses again? (nothing is blown to my knowledge)

ANY HELP OR TROUBLE SHOOTING ADVICE FOR WHY MY AC CONDENSER FAN IS NOT COMING ON WOULD BE GREATLY APPRECIATED. (sorry for the all caps)

Slowcrash_101

There's a pressure safety switch on the AC compressor. But it only comes on if high side pressure is very high like 300psi. Higher than that and it'll pop like a fuse.

Billman250

Engine cold, key on, AC button on, one fan light on, engine not running:

Do both fans run at this time? Compressor operation is irrelevant for the listed test parameters.

Chuck S

I assume everything was working before you changed out the radiator? Both fans should activate when the engine gets up to normal running temperature and when using the AC. Both fans, never just one, from what I can tell.

For AC the 2006 and later cars activate both fans when (1) ignition On, (2) AC button depressed and (3) fan set to any speed -- one or more green lights. This is regardless of the engine running or not. You need to follow the trouble shooting guides in the service manual.

(Bill and I were typing at the same time!)

-- Chuck

R00567

Engine Cold, Key ON, AC button ON, one fan flight ON, engine is not running = driver side fan only powers up, not the passenger side / Right radiator fan.

^^ the driver fan that comes on responds if i turn ON or OFF the AC button. *(isnt that the cooling fan though?) thats why i am stumped :-(

RacerXI

The manual says the drivers' side is the a/c fan. (That's news to me)
You've determined both fans work, but it seems the passenger side is not getting a signal to turn on. Rad fan wire color is blu/blk and ac fan is blu/yel also.
Test both rad and ac relays and see "what" fan comes on if you would? Can you power the passenger fan from the radiator fan relay? If yes, I'd say try checking continuity between the fan switch and the relay. Hope that helps.

R00567

You sure the driver side is the AC fan bro? Then now i have to hunt down why my cooling fan is not energizing.

I will try jumping relays and see what happens (Based on the labels in the fuse box), and report my findings back here.

Can any one else confirm the driver side fan is the AC condenser fan? Thanks again for all the help!

Chuck S

Based on tracing the wiring diagrams I believe both fans activate anytime a fan is needed in 2006 and later cars. This was confirmed on my 2006 car in operation. Earlier cars may use one fan for engine cooling and add the second fan for AC. I didn't pay much attention to that diagram as I have an '06.

-- Chuck

Billman250

Bottom line:

cold engine, key on, ac button/light on, 1 fan light on.

Both fans should run. This goes for 00-09 S2000s.

If your right fan is not coming on, trace lack of power to right fan to origin.

R00567

Thanks again Billman! I will double check this tomorrow and report my findings back. I appreciate your help!