Welcome to the North American Subaru Impreza Owners Club Thursday April 24, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Electrical & Lighting

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 05-14-2009, 06:58 AM   #1
RP31
Scooby Specialist
 
Member#: 123574
Join Date: Aug 2006
Chapter/Region: MWSOC
Location: Lisle, IL
Vehicle:
2005 2.6L 9:1 425WHP
CGM STi

Default Electronic climate control gurus: I need your help!

Or anyone who has a detailed wiring diagram of this system...

This is a fun one. My climate control has pretty much stopped working, although it will start working again if I hit a bump or (sometimes) honk my horn. Yes at this point I expect you to be thinking "WTF?" I'm right there with you.

More details/examples:
Most of the time, my outside temperature gauge will read 100+ degrees though it's much cooler outside. I've already checked and replaced the temperature sensor by the radiator.

A few months ago I was sitting at a red light behind another car. The light turned green, car in front of me hesitated too long for my liking. I honked the horn. Suddenly I had cool air blowing from the vents! I glanced down and my outside temperature reading was quickly dropping to ambient temp. WTF. This sort of thing has been inconsistently repeatable. My coworkers think it's hilarious. "Oh, you're hot back there? Here, let me try honking the horn to see if that helps..." If it works, great. If not, the windows get rolled down.

Recently I've also noticed that hitting bumps in the road can cause the climate control to start working again. On my way to work this morning, for example, my outside temp gauge read 122 degrees and I wasn't getting any air from the vents. I ran over some train tracks and had cool air. Sure enough, the outside temperature gauge was dropping fast. It eventually settled on ambient temperature, ~58 degrees.

My car does not have aftermarket horns or anything wired into the climate control system. It does have an aftermarket alarm (I installed it 5 years ago), but that is not wired into the horns or climate control. This has only started happening within the past 6 months or so, and I have not changed anything electrical on the car in that period of time. This seems like it has to be a loose connection some where, but I have no idea where to look. And the fact that honking the horns triggers it is even more confusing. Maybe there's a relay shared between the climate control and the horns/temperature sensor?

Any help would be greatly appreciated. I wouldn't even bother taking the car some place for an issue like this... It's way too inconsistent.
* Registered users of the site do not see these ads.
RP31 is offline   Reply With Quote
Old 05-14-2009, 11:00 AM   #2
Cougar4
Scooby Specialist
 
Member#: 53443
Join Date: Jan 2004
Location: Anchorage, AK
Vehicle:
2001 LL Bean Outback
Winestone

Default

I suggest you remove the ground connections to the chassis under the hood and clean them. If that doesn't work then clean the grounds under the dash. Hopefully that will help clear this trouble.
Cougar4 is online now   Reply With Quote
Old 05-14-2009, 11:05 AM   #3
RP31
Scooby Specialist
 
Member#: 123574
Join Date: Aug 2006
Chapter/Region: MWSOC
Location: Lisle, IL
Vehicle:
2005 2.6L 9:1 425WHP
CGM STi

Default

That's easy enough that I'll try it out as a troubleshooting step. Do you have previous experience that made you suggest this, or just a hunch? It certainly couldn't hurt, just wondering if I should get my hopes up beforehand.
RP31 is offline   Reply With Quote
Old 05-14-2009, 11:39 AM   #4
Cougar4
Scooby Specialist
 
Member#: 53443
Join Date: Jan 2004
Location: Anchorage, AK
Vehicle:
2001 LL Bean Outback
Winestone

Default

Bad grounds have caused many problems like this. It might not solve the trouble but then it just might.
Cougar4 is online now   Reply With Quote
Old 05-14-2009, 03:51 PM   #5
Uncle Scotty
Scooby Guru
 
Member#: 16200
Join Date: Mar 2002
Vehicle:
OK Houston
we have an Uncle

Default

was there ANYTHING done to the car just prior to this issue starting??

ANYTHING????
Uncle Scotty is offline   Reply With Quote
Old 05-14-2009, 04:39 PM   #6
RP31
Scooby Specialist
 
Member#: 123574
Join Date: Aug 2006
Chapter/Region: MWSOC
Location: Lisle, IL
Vehicle:
2005 2.6L 9:1 425WHP
CGM STi

Default

Hmmm... Nothing out of the ordinary. Winter wheel/tire swap, washer fluid change, and an oil change. I haven't done any real changes to the car in years.
RP31 is offline   Reply With Quote
Old 05-14-2009, 05:48 PM   #7
Uncle Scotty
Scooby Guru
 
Member#: 16200
Join Date: Mar 2002
Vehicle:
OK Houston
we have an Uncle

Default

no new gauges....or new 'system' or nothing electrical, then???
Uncle Scotty is offline   Reply With Quote
Old 05-14-2009, 06:03 PM   #8
RP31
Scooby Specialist
 
Member#: 123574
Join Date: Aug 2006
Chapter/Region: MWSOC
Location: Lisle, IL
Vehicle:
2005 2.6L 9:1 425WHP
CGM STi

Default

Unfortunately not. Going to clean up the grounds now. May take a few days to know whether or not that solves the problem... Climate control was still working after the drive home.
RP31 is offline   Reply With Quote
Old 05-14-2009, 08:36 PM   #9
RP31
Scooby Specialist
 
Member#: 123574
Join Date: Aug 2006
Chapter/Region: MWSOC
Location: Lisle, IL
Vehicle:
2005 2.6L 9:1 425WHP
CGM STi

Default

Update: Spent about an hour cleaning all of the grounds. Ate dinner, watched some TV, reconnected the negative battery cable and started up the car.

1) Temperature gauge read 110 degrees (read ambient temp when I parked the car).
2) Honking the horn once dropped the temperature reading to 66 degrees.
3) The thermostat in my garage also read 66 degrees.
RP31 is offline   Reply With Quote
Old 05-14-2009, 09:02 PM   #10
Cougar4
Scooby Specialist
 
Member#: 53443
Join Date: Jan 2004
Location: Anchorage, AK
Vehicle:
2001 LL Bean Outback
Winestone

Default

Since cleaning the ground connections didn't help I suggest you next remove the cluster and disconnect the connections to it, and then reconnect them back up. Maybe the trouble is due to a faulty connection there. There should be a voltage regulator for those circuits and it is inside the cluster.
Cougar4 is online now   Reply With Quote
Old 05-14-2009, 09:07 PM   #11
RP31
Scooby Specialist
 
Member#: 123574
Join Date: Aug 2006
Chapter/Region: MWSOC
Location: Lisle, IL
Vehicle:
2005 2.6L 9:1 425WHP
CGM STi

Default

That could help, but the most curious thing is definitely how the horn "activates" the temperature sensor without the car moving. I'd like to figure out how they might be connected. Something like that doesn't strike me as a loose connection.
RP31 is offline   Reply With Quote
Old 05-14-2009, 10:30 PM   #12
Uncle Scotty
Scooby Guru
 
Member#: 16200
Join Date: Mar 2002
Vehicle:
OK Houston
we have an Uncle

Default

vibration of the horn itself....mebbe???
Uncle Scotty is offline   Reply With Quote
Old 05-15-2009, 03:04 AM   #13
SVXdc
Scooby Specialist
 
Member#: 25837
Join Date: Oct 2002
Chapter/Region: South East
Location: Atlanta, GA
Vehicle:
1996 SVX L AWD
Laguna Blue Pearl

Default

Yeah, if a bump can cause it to start working, sounds like a bad connection or bad wire somewhere. Perhaps a wire that's been severed, but gets bumped/vibrated back into making contact.

You could try vibrating the frame next to the temp sensor (with something like sawzall or jigsaw without the blade). That might tell you if it's strictly physical (and not related to the horn's electrical circuit).

Since you're seeing wacky temp readings, look closely at those wires trace them back to the A/C control module. Good wiring diagrams would help. A dealer might print off some of the pages for you if you ask nicely.
SVXdc is offline   Reply With Quote
Old 05-15-2009, 08:31 AM   #14
RP31
Scooby Specialist
 
Member#: 123574
Join Date: Aug 2006
Chapter/Region: MWSOC
Location: Lisle, IL
Vehicle:
2005 2.6L 9:1 425WHP
CGM STi

Default

Update from the morning commute: I decided to test out more possible horn connections by disconnecting the horns. When I first started my drive, climate control was working. Hit some bumps and it stopped working. Pressing the horn multiple times did nothing. Eventually hitting some other bumps reactivated the climate control.

Right now front end vibration near the temp sensor is looking like the most likely culprit. Just have to trace it back.
RP31 is offline   Reply With Quote
Old 05-15-2009, 12:19 PM   #15
Cougar4
Scooby Specialist
 
Member#: 53443
Join Date: Jan 2004
Location: Anchorage, AK
Vehicle:
2001 LL Bean Outback
Winestone

Default

Here is another thing you could try. The earlier versions had a couple of major wire connections near the battery area. I'm not sure if the newer ones are the same way or not but assume they are. Some folks have solved this kind of trouble by disconnecting and reconnecting the connectors. You can also try using a screwdriver handle to tap on suspected trouble areas to see if you can pin the trouble area down.
Cougar4 is online now   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Cell phone gurus: Need your help!! JM530 Mid West Subaru Owners Club Forum -- MWSOC 5 02-27-2008 10:34 PM
OT Web Gurus: Need your help kage Off-Topic 3 03-08-2006 06:02 PM
suspension gurus: I need your opinion eyeballs Brakes, Steering & Suspension 23 12-03-2003 05:25 PM
ATTN: electronic masters i need your help White 2.5rs Electrical & Lighting 4 09-16-2003 12:41 PM
Which electronic boost controller is best in your opinion? Diversion Factory 2.0L Turbo Powertrain 26 05-18-2002 12:06 AM


All times are GMT -4. The time now is 01:17 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.