Welcome to the North American Subaru Impreza Owners Club Monday March 18, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Engine Management & Tuning > Commercial ECU Reflashes

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.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 02-21-2007, 12:17 PM   #1
STI EXTC
Scooby Newbie
 
Member#: 110777
Join Date: Mar 2006
Location: NoVA
Vehicle:
2010 STi
black

Default CEL Fix = No Illumination settings in the 04 STi ?

I recently had my 2004 STi tuned, and one of the things we did was remove the P420 CEL from appearing on the dash. 200 miles later, that seems to have worked as that code has still not reared it's ugly head. However, I cannot change the illumination settings in the dash (brightness/dimness). I'm guessing that's a side effect? I guess I should go the spark plug anti fouler route eh?
* Registered users of the site do not see these ads.
STI EXTC is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 02-21-2007, 12:29 PM   #2
x99percent
Scooby Specialist
 
Member#: 27108
Join Date: Oct 2002
Chapter/Region: MWSOC
Location: Detroit-ish, MI
Vehicle:
2004 STi
2004 A4

Default

*TOTALLY* unrelated.
x99percent is offline   Reply With Quote
Old 02-21-2007, 02:03 PM   #3
STI EXTC
Scooby Newbie
 
Member#: 110777
Join Date: Mar 2006
Location: NoVA
Vehicle:
2010 STi
black

Default

Quote:
Originally Posted by x99percent View Post
*TOTALLY* unrelated.
Really? Why do you say that? I only suspected the tuning change because that's the only thing that has changed on my car in the last week or so. A few weeks back I had a sound system installed, but I'm 95% certain I could change my illumination settings after that. The reason I noticed this issue is because the dash is now dimmer than I normally had it (I used to have it on the highest illumination). Thoughts?
STI EXTC is offline   Reply With Quote
Old 02-21-2007, 02:10 PM   #4
gabedude
Scooby Guru
 
Member#: 10108
Join Date: Sep 2001
Chapter/Region: NWIC
Location: Portland, OR
Vehicle:
1874 Bicycle

Default

Do you really think a denso ECU cares about your dash illumination controls? If so, grab the wiring diagram and show me the inputs and outputs to the ECU to change the lighting on the dash.
gabedude is offline   Reply With Quote
Old 02-21-2007, 03:17 PM   #5
Master2192
RIP 10/12/83 to 02/10/08
Scooby Specialist
 
Member#: 83254
Join Date: Mar 2005
Chapter/Region: NWIC
Location: Roy, Washington
Vehicle:
98 2.5 RS
04 WRX

Default

Quote:
Originally Posted by STI EXTC
A few weeks back I had a sound system installed, but I'm 95% certain I could change my illumination settings after that. The reason I noticed this issue is because the dash is now dimmer than I normally had it (I used to have it on the highest illumination). Thoughts?
I think its your Stereo. When I was wiring in the LC-1 in my friends car I picked the ground for the illumination circuit and it worked fine until we turned on the lights, then it would blow the illumination fuse. My bet is your installer did something similar since the Subaru's use a switched to ground system for the illumination of the dash. Try turning off the stereo and see if the illumination works properly.
Master2192 is offline   Reply With Quote
Old 02-21-2007, 08:13 PM   #6
TMessick
Scooby Newbie
 
Member#: 882
Join Date: Feb 2000
Location: Michigan
Vehicle:
2004 WRX Wagon
very blue

Default

Quote:
Originally Posted by gabedude View Post
Do you really think a denso ECU cares about your dash illumination controls? If so, grab the wiring diagram and show me the inputs and outputs to the ECU to change the lighting on the dash.
FWIW, federal regulations stipulate that the check engine light cannot be dimmed within the instrument cluster. On some of the programs I've worked on, since the check engine light was on the same dimmer circuit as the rest of the dash, that meant that when the CEL was lit, you couldn't dim the dash at all (early on in development the dash didn't do this, when we got our newer test mules they did and I complained and got this answer)

Anyhew, since the CEL is lit by a bus message, it is certainly possible that a part of this message inhibits dimming and is not "blocked" by the CEL fix.

If you really wanted to check, you could reset the ECU and see if dash light control comes back. Alternatively, just flash back to stock and see if dash control comes back...
TMessick is offline   Reply With Quote
Old 02-21-2007, 08:16 PM   #7
TMessick
Scooby Newbie
 
Member#: 882
Join Date: Feb 2000
Location: Michigan
Vehicle:
2004 WRX Wagon
very blue

Default

Of course, if I actually read your whole post, I'd have noticed that you're dash is now dimmer than before, which is the opposite condition to what we saw... In that case, (and because I've not heard of anyone else ever complaining of a similar problem) I'd say the interaction is unlikely...
TMessick is offline   Reply With Quote
Old 02-21-2007, 09:15 PM   #8
gabedude
Scooby Guru
 
Member#: 10108
Join Date: Sep 2001
Chapter/Region: NWIC
Location: Portland, OR
Vehicle:
1874 Bicycle

Default

Quote:
Originally Posted by TMessick View Post
FWIW, federal regulations stipulate that the check engine light cannot be dimmed within the instrument cluster. On some of the programs I've worked on, since the check engine light was on the same dimmer circuit as the rest of the dash, that meant that when the CEL was lit, you couldn't dim the dash at all (early on in development the dash didn't do this, when we got our newer test mules they did and I complained and got this answer)

Anyhew, since the CEL is lit by a bus message, it is certainly possible that a part of this message inhibits dimming and is not "blocked" by the CEL fix.

If you really wanted to check, you could reset the ECU and see if dash light control comes back. Alternatively, just flash back to stock and see if dash control comes back...
You missed something there good buddy. The cell fix is in the ECU ROM image. The ecu never sends the signal to the pin to trigger the CEL to come on. The ECU don't just "turn off the light". Each CEL can be disabled independently.

Now if the tuner did something to disable the CEL outside of the ECU.... Who the hell knows.

Edit:

Well, if the ECU is sending a trouble code command packet out onto the bus with some missing information, then that would be a bug in the cell fix itself. AFIK, the fixes are for specific trouble codes. That would lead me to believe that a packet is never sent out to trigger a trouble code CEL. One would think that if you disable a trouble code in the ECU rom, then the ecu would never invoke the function to turn on the CEL.

Last edited by gabedude; 02-21-2007 at 10:09 PM. Reason: More thought
gabedude is offline   Reply With Quote
Old 02-21-2007, 10:16 PM   #9
TMessick
Scooby Newbie
 
Member#: 882
Join Date: Feb 2000
Location: Michigan
Vehicle:
2004 WRX Wagon
very blue

Default

Ahh, didn't realise the WRX still used old-school hardwired CEL. I think the last product i worked with that did that was like 1996 or so...

Newer (apparently non-subaru) crap that uses CAN or other bussed communications between the ECU and cluster can have the funky interactions of which I spoke. We basically ran two embedded bus messages, one for the CEL and one to inhibit cluster dimming, so I was thinking the CEL fix could inhibit one of the bussed messages but not the other. Siunce you're looking at a single hardwired input/output, it's either there or it's not (no interaction). In the end, my entire comments have no bearing on the OP's problem.. Whoops.

gabedude's subaru knowledge > my subaru kowledge

So yeah, OP probably has something bunged up on the dimmer wiring...
TMessick is offline   Reply With Quote
Old 02-22-2007, 10:07 AM   #10
gabedude
Scooby Guru
 
Member#: 10108
Join Date: Sep 2001
Chapter/Region: NWIC
Location: Portland, OR
Vehicle:
1874 Bicycle

Default

Quote:
Originally Posted by TMessick View Post
Ahh, didn't realise the WRX still used old-school hardwired CEL. I think the last product i worked with that did that was like 1996 or so...

gabedude's subaru knowledge > my subaru kowledge
I really don't know if its just a pin or sent out on a bus signal (That was an ASSumption. I would have to look at the ECU pinout). What I do know is that the trouble code fixes are in the ECU rom. The ECU chip uses this table to invoke the CEL function. There is not a global inhibit CEL light fix. If there was, then what you said would make sense.
gabedude is offline   Reply With Quote
Old 02-22-2007, 02:59 PM   #11
STI EXTC
Scooby Newbie
 
Member#: 110777
Join Date: Mar 2006
Location: NoVA
Vehicle:
2010 STi
black

Default

Quote:
Originally Posted by gabedude View Post
Do you really think a denso ECU cares about your dash illumination controls? If so, grab the wiring diagram and show me the inputs and outputs to the ECU to change the lighting on the dash.
No need to be rude... never did I state that I unequivocally knew what the ECU did or did not control, hence the question. Thanks for being a jackass though.
STI EXTC is offline   Reply With Quote
Old 02-22-2007, 03:02 PM   #12
STI EXTC
Scooby Newbie
 
Member#: 110777
Join Date: Mar 2006
Location: NoVA
Vehicle:
2010 STi
black

Default

Quote:
Originally Posted by Master2192 View Post
I think its your Stereo. When I was wiring in the LC-1 in my friends car I picked the ground for the illumination circuit and it worked fine until we turned on the lights, then it would blow the illumination fuse. My bet is your installer did something similar since the Subaru's use a switched to ground system for the illumination of the dash. Try turning off the stereo and see if the illumination works properly.
Thanks for the helpful response, I'll try that and post back the results.
STI EXTC is offline   Reply With Quote
Old 02-23-2007, 11:38 AM   #13
gabedude
Scooby Guru
 
Member#: 10108
Join Date: Sep 2001
Chapter/Region: NWIC
Location: Portland, OR
Vehicle:
1874 Bicycle

Default

Quote:
Originally Posted by STI EXTC View Post
No need to be rude... never did I state that I unequivocally knew what the ECU did or did not control, hence the question. Thanks for being a jackass though.
Calling people names isn't going to get you very far here. If you read the rest of the post, you may have noticed that two of us with some good knowledge of electronics and software in car computers pondered your question for awhile. That means that I even cared enough about your question to give a more elaborate answer and take time out of my life to do so. My take is that the trouble codes are in the ECU, therefor the function to send out the signal to light the CEL is never sent. If you don't understand what that means, thats cool. Since you are new, get used to a little bit of ribbing until you gain more knowledge. Its all in fun, don't take it so seriously man.

gabedude is offline   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
Radio blank that came in the 04 Sti... Pacobeagle Private 'Wanted' Classifieds 5 10-03-2006 03:20 PM
Is the ABS controller in the 04 STi one part with the hydraulic pump? Rustyr6 Brakes, Steering & Suspension 8 12-11-2005 09:20 AM
pinging in the 04 sti gotparts? Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo) 18 09-21-2005 12:13 PM
What's the use of the B28 in the 04 STi cluster used for? V6 Electrical & Lighting 1 08-08-2005 04:12 AM
Mechanical CEL fix no workie cabin Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 11 04-26-2004 03:32 PM

All times are GMT -4. The time now is 10:40 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.