Cooling fan on with ignition - RX8Club.com

Go Back  RX8Club.com > General Topics > RX-8 Discussion
Reload this Page >

Cooling fan on with ignition

Notices
RX-8 Discussion General discussion about the RX-8 that doesn't fit in one of the specialty forums.

Cooling fan on with ignition

Old 01-20-2019, 04:42 PM
  #1  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
Cooling fan on with ignition

Hi my S2 with ignition on only the cooling fan comes on and stays on. What can I check I just disconnected cooling fan control mod as I thought this might be the issue but wasn't. Temp gauge went over half when idling in 107f heat so unsure if other fan is coming on. Cheers
Code P0480 and P0481 was noted
Sydo is offline  
Old 01-20-2019, 05:21 PM
  #2  
Chief Meteobraptologist
iTrader: (1)
 
Loki's Avatar
 
Join Date: Jun 2009
Location: Montreal
Posts: 4,340
Thanked 274 Times in 242 Posts
I'm pretty sure it's normal for the fan to come on if you turn on the ignition and the engine is warm. It may even do it cold, I'm not sure, but depending on what you were doing before you observed this, it may be normal.
In the normal case it will turn off after a bit of time. Like 20-30 seconds. If it doesn't, and the engine is cold, and the fan just keeps running for minutes, that's weird.

I'm not sure how P0480/P0481 are actually detected by the ECU, but one mechanism may be that it turns on the fans (or thinks it does), but the coolant temperature doesn't go down. On the 8 it may have another mechanism, like some kind of load reading on the circuit, but long story short, the ECU thinks the fan relays are not working. So while you've disconnected the mod, is it possible you need to reconnect the original wiring?

Last edited by Loki; 01-20-2019 at 05:25 PM.
Loki is online now  
The Following User Says Thank You to Loki For This Useful Post:
Sydo (01-20-2019)
Old 01-20-2019, 05:52 PM
  #3  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
I'm going to buy a new hose where sensor is tapped in. That mod isn't required on S2 apparantly.

Last edited by Sydo; 01-20-2019 at 07:48 PM.
Sydo is offline  
Old 01-20-2019, 06:33 PM
  #4  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
....

I took out top right relay in pic which is cooling fan 3 for s2 and it cut out. Went back on when refitted
Sydo is offline  
Old 01-20-2019, 07:44 PM
  #5  
转子之魂
 
UnknownJinX's Avatar
 
Join Date: Apr 2017
Location: Victoria, BC
Posts: 1,927
Thanked 278 Times in 256 Posts
Here is how the cooling fan controls work in an S2 in tabulated form:



Originally Posted by Loki View Post
I'm pretty sure it's normal for the fan to come on if you turn on the ignition and the engine is warm. It may even do it cold, I'm not sure, but depending on what you were doing before you observed this, it may be normal.
In the normal case it will turn off after a bit of time. Like 20-30 seconds. If it doesn't, and the engine is cold, and the fan just keeps running for minutes, that's weird.

I'm not sure how P0480/P0481 are actually detected by the ECU, but one mechanism may be that it turns on the fans (or thinks it does), but the coolant temperature doesn't go down. On the 8 it may have another mechanism, like some kind of load reading on the circuit, but long story short, the ECU thinks the fan relays are not working. So while you've disconnected the mod, is it possible you need to reconnect the original wiring?
Per service manual, this is how the P0480 and P0481 work:



Naturally, it covers how to repair the codes. It's mostly checking open circuits, shorts, poor connections, etc. ASH8 has the service manuals posted up in this forum.
UnknownJinX is offline  
The Following User Says Thank You to UnknownJinX For This Useful Post:
Sydo (01-20-2019)
Old 01-20-2019, 08:16 PM
  #6  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
Thanks Jinx so according to that my fan shouldn't be on at start up ?
Sydo is offline  
Old 01-20-2019, 08:36 PM
  #7  
转子之魂
 
UnknownJinX's Avatar
 
Join Date: Apr 2017
Location: Victoria, BC
Posts: 1,927
Thanked 278 Times in 256 Posts
Definitely not on a cold start unless you have your A/C on. Hot starts will depend on the ECT, as the table indicates.
UnknownJinX is offline  
Old 01-20-2019, 08:47 PM
  #8  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
Aircon off. I have swapped around relays and the same. The fan that is operating when cold is number 3 in fuse box
Sydo is offline  
Old 01-21-2019, 12:29 AM
  #9  
转子之魂
 
UnknownJinX's Avatar
 
Join Date: Apr 2017
Location: Victoria, BC
Posts: 1,927
Thanked 278 Times in 256 Posts
https://www.rx8club.com/series-ii-te...manual-247192/

Download the workshop manual and start following their procedures for troubleshooting. I would think there is a short somewhere in the circuit.
UnknownJinX is offline  
The Following User Says Thank You to UnknownJinX For This Useful Post:
Sydo (01-21-2019)
Old 01-22-2019, 02:59 AM
  #10  
Modulated Moderator
iTrader: (3)
 
dannobre's Avatar
 
Join Date: Feb 2004
Location: Smallville
Posts: 12,662
Thanked 83 Times in 80 Posts
Is your coolant temp sensor OK?
dannobre is offline  
Old 01-22-2019, 03:16 AM
  #11  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
Originally Posted by dannobre View Post
Is your coolant temp sensor OK?
Not sure mate going over it now. How can we check ?
Sydo is offline  
Old 01-22-2019, 03:48 AM
  #12  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
Temp is reading on scanner ok
Sydo is offline  
Old 01-22-2019, 10:19 AM
  #13  
^^^ Fluent in snark.
 
NotAPreppie's Avatar
 
Join Date: Mar 2006
Location: Chicago, IL, USA, North America, Earth, Sol System, Sector ZZ9 Plural Z Alpha, Milkyway, Universe
Posts: 3,083
Thanked 386 Times in 313 Posts
I've heard of people wiring up a manual switch somewhere in reach of the driver. Any chance the PO did this?
NotAPreppie is online now  
Old 01-22-2019, 12:40 PM
  #14  
Water Foul
 
Steve Dallas's Avatar
 
Join Date: May 2013
Location: Republic of Texas
Posts: 2,202
Thanked 145 Times in 117 Posts
Originally Posted by NotAPreppie View Post
I've heard of people wiring up a manual switch somewhere in reach of the driver. Any chance the PO did this?
That would be the fans on low mod. I did it. Works great when the AC is off. If this was done, there would be an extra wire running from the switch to the relay box, and another wire running from the switch to ground.
Steve Dallas is offline  
Old 01-22-2019, 03:16 PM
  #15  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
Had a look no switch. I wonder if this problem interferes with other fan speeds ?
Sydo is offline  
Old 01-23-2019, 10:36 AM
  #16  
^^^ Fluent in snark.
 
NotAPreppie's Avatar
 
Join Date: Mar 2006
Location: Chicago, IL, USA, North America, Earth, Sol System, Sector ZZ9 Plural Z Alpha, Milkyway, Universe
Posts: 3,083
Thanked 386 Times in 313 Posts
Who knows? You get those electrical pixies dancing in a circle and all bets are off.
NotAPreppie is online now  
Old 01-24-2019, 04:29 PM
  #17  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
Bought a new coolant temp sensor will try that
Sydo is offline  
Old 01-24-2019, 04:37 PM
  #18  
Registered
Thread Starter
 
Join Date: Sep 2018
Location: Down Under
Posts: 249
Thanked 6 Times in 6 Posts
Originally Posted by UnknownJinX View Post
Here is how the cooling fan controls work in an S2 in tabulated form:





Per service manual, this is how the P0480 and P0481 work:



Naturally, it covers how to repair the codes. It's mostly checking open circuits, shorts, poor connections, etc. ASH8 has the service manuals posted up in this forum.
Would you know where cooling fan relay 4 and 5 are ?
Sydo is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rotarywanker
RX-8 Parts For Sale/Wanted
0
11-07-2015 06:17 PM
flaps720
Series I Tech Garage
2
07-21-2010 12:46 PM
Lock & Load
Australia/New Zealand Forum
21
12-05-2003 07:41 AM
labrat
Australia/New Zealand Forum
4
09-17-2003 11:12 PM


Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Cooling fan on with ignition


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.