takahashi

I have brought myself an HKS fan controller, aiming to turn on the fan that the temperature that I want. It only cost AUD$225 plus a AUD$80 oil temp sensor.

Cheap Yeah but it is yet to be installed and have a diagram to install to an RX-8.

But looking at the installation in Japanese :p I can be done.
Since it is connected with the wire in the ECU harness.

I have seen and actually got copies of the PCM pin location from the RX-8 repair manual.

It is connecting to Earth, Power, Car speed, Coolant temp, Main fan and Supplimentary fan. If there is a low_medium_ and high speed setting of each fan. Then there are multiple maps possible (as in different generation of FD3S.

My only concern:

Is the RX-8 fan similar to RX-7 (FDs)? FD has a low, medium and high speed. And I look at their PCM diagram they have Fan replay No.3, which we have too! Does that mean we have a 3 speed fan for the 2 fans??? If it is then it is very hard to do .


If not, what is it then?

I don't want to give up and can use it rather than given it to my friend. It is a matter of working it out, me thinks

StealthTL

iTrader: (1)

The control scheme is worse than you imagine, it looks like you can only take control of all of it or leave it alone!

There are three relays, but only TWO control inputs

- relay 2 by itself runs fan#2 on high speed

- relay 1 by itself puts current through BOTH fans in SERIES, so both run on slow speed

-when both relays pull in it re-routes the ground of fan #1 (thru relay 3) and both fans run on high speed

and worse for you, all three relays have power all the time and are GROUNDED by the computer, to run.

It's all on page 26 of the manual, (I had to figure it all out when one of my cooling fans burned out) very well engineered, but hard to externally control! :o

S

takahashi

It really sound like the later FDs...

Damn. Stealth... I will try to scan what they have done to the FDs and see what you think.
They have diagram for 3 generations of FD.... very confusing. I guess RX-8 will be simiarly confusing.

I think the bottom line will be wait until HKS figure it out. It is only AUD$300. I guess I can leave it for now --- I guess my mechanic friend next to me is having a sigh of relief LOL :D :o :p :D

army_rx8

is this to control teh radiator fan...or are you adding a fan to your oil coolers? if it's for the radiator fan why would you need an oil temp sensor for that..i would think you would rather have a water temp sensor? hmm or i think i'm just confused

takahashi

hehe

It is a fan controller to control the radiator fan.

However, it has an extra function to sense (just record any temperature). It can be oil temp, air temp, intake temp or catalyst temp as long as you can hook it up. So I choose oil temp as there is no sensor to it. Not perfect as the Defi meter, which I now think I should get instead.

The unit itself, once hook up, can show the coolant temperature and from that temperature, the fan can be switched on or off, or in the case of the FD3S RX-7s, low/med/high on each fan.

It takes a map to do me thinks. I will wait until HKS have work out the wiring for the RX-8s. I would not be surprised if it is extremely or even the same with the FD RX-7s, but which one??? I have 3 patterns of the FDs (diff generations) in the installation manual......

takahashi

Sorry about the size of the pic
But there it is the pic of it

http://www.hksusa.com/images_products/1748.jpg

mzdoggmann

Anyone had any problems (or heard of problems) of the Rotaries having a propensity to overheat, esp. in high rev environments or tropical locations??

army_rx8

^are we talking about the new generation (13b-msp) or all rotarys in general? (ie al the others 10a, 12a, 13b, 13b-rew, 13b-tt, etc.)?

takahashi

Even in the 13B-MSP, overheating is highly possible in normal congested driving.

Racing wise, in a hot day, the coolant temperature can go up to 140 degree Cel. It is way too hot.

The RX-8 Party Race in Japan requires upgrade of oil cooler and radiator (MazdaSpeed) before entering the race.... it speaks so much about cooling of a rotary

I guess I just go straight to a 3 layer Bass radiator rather than playing with the wiring. I have not yet had a chance to scan that schematic diagram I promised. Feel a bit unwell so I slept 12 hours straight last night.

mzdoggmann

I'm looking to buy a '04 RX-8 w/ the 238 hp 6 spd engine... want to see others who have one and any experiences they had w/ overheating issues.
I live in L.A. so am concerned about those Hot summer days when I'm cruising around or light racing.

takahashi

I use the sCANalyser in Hong Kong over a humid warm day 26 deg Cel and 85% humidity.

Although it is not a critical level. The coolant temp did go above 98 degree Cel in the congested tunnel and about 92-93 degree on the motorway. It is way to hot for normal driving.

I made a mistake quoting the oil temp previously. It is above 110 degree Cel when the coolant temp is way too hot.

I think in LA, even it is hot, it is ok during crusing and light racing. It is when either you are doing 10 + hot laps or you are in a congestion, then the coolant temp will climb.

Therefore, it is good to have a oil and water temp for any circumstances === an excuse to my Mrs.

mzdoggmann

Got it... Guess rotary designs just attracts more heat. Guess you just have to be careful with these.