Malfunction Lamp - P0685 - AcuraZine Community

Go Back   AcuraZine Community > AcuraZine TSX Community > First Generation TSX Discussion (2004-2008) > Problems & Fixes
Log In 

Malfunction Lamp - P0685

LinkBack Thread Tools Search this Thread
Old 02-10-2011, 07:45 AM   #1
Registered Member
Trader Rating: (0)
Join Date: Jul 2009
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Malfunction Lamp - P0685

(TSX 2004 w/ nav)

My Malfunction indicator lamp came on. Took it to my mechanic (not dealer) and the code was P0685. He said to get an ECM relay from the dealer and he would fix it.
When I called Acura to order the part, they want me to come and have them check it out (& I'm sure they want me to use their expensive services instead.)

Is my mechanic right - that all I need is the ECM relay? I don't want to be taken advantage of by the dealer or my mechanic.

BTW, my navigation system has been restarting itself as i'm driving. Are the 2 issues related? Thanks!
rxtwo83 is offline   Reply With Quote
Old 02-10-2011, 11:20 PM   #2
in the 24th and a half...
DuckDodgers's Avatar
Trader Rating: (0)
Join Date: Mar 2006
Location: TX
Age: 50
Posts: 851
Thanked 36 Times in 35 Posts
Hum...."P0685 - Engine Control Module (ECM)/Powertrain Control Module (PCM) Power Control Circuit Malfunction"

Diagonostic procedure clears the DTC and sees if it reoccurs. Intermittent DTC indicates a loose connection in IGP line connectors...if the DTC does reoccur, "intermittent failure, the system is OK at this time"...if it reoccurs "Update ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known good ECM/PCM, replace the original ECM/PCM."

Note that the HDS is required for these actions, does this independent mechanic have a HDS?

There are actually 2 ECM relays, at about $35 each...and one ECM at about $540...

You can tell the dealer no, but the relays are yours and yours alone after you buy them (that's the usual electrical parts policy). If it's a relay, figure the diagnostic cost should about cover the repair...if it isn't, your independent can't save you any money if he doesn't have access to an HDS unit. Even then, it's not likely to be a massive cost savings. I like independent mechanics, but this screams dealer.

On the Navi, not sure. That is not a listed error, try entering diagnostic mode and checking things out:

If battery has not been disconnected (you are not at code or gps aquire screen);

Ignition switch on, press and hold "Menu", "Map/Guide", and "Cancel" buttons together for 5 will go to diagnostic screen.

If the battery was disconnected and you are at either screen above; hold down "Menu" and "Zoom out" buttons, then at "Navi Link Screen" push joystick to get to "Functional Setup menu", the touch "Return" icon to get the menu.

It's a very useful trick!
DuckDodgers is offline   Reply With Quote
Old 10-02-2011, 02:04 PM   #3
Regional Coordinator (Texas)
nspec_ya4's Avatar
Trader Rating: (38)
Join Date: Aug 2008
Location: Houston
Age: 29
Posts: 4,290
Thanked 602 Times in 308 Posts
did you ever figure out exactly what the problem was?
01'CLS 3.6L 6 Speed>07'C6Z>06'SRT10Coupe>13'GTS

nspec_ya4 is offline   Reply With Quote
Old 10-03-2011, 11:00 AM   #4
Registered Member
Trader Rating: (0)
Join Date: Jul 2009
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
I took it back to the dealer and it turns out that is was my battery. I got a battery from O'Reilly's and apparently it was bad. (Acura did the battery check and I wasn't getting the power I should have been). so fortunately it turned out to be a very inexpensive problem.
rxtwo83 is offline   Reply With Quote


Similar Threads
Thread Thread Starter Forum Replies Last Post
Modesta BC-04 on a Maritime Blue - Paint to Sample - Porsche 911 GT3 detailersdomain Wash & Wax 3 10-09-2015 10:13 PM
ABS and VSA intermittent malfunction hedzup First Generation RL (1996-2004) 1 09-30-2015 12:18 AM
2nd gen TSX head unit install to help upgrade "tech" feel? Eggs999bacon Second Generation TSX Discussion (2009+) 10 09-24-2015 10:08 AM
Nissan: Gripz News Yumcha Automotive News 4 09-21-2015 08:44 AM
Tranny only 2 years old, pressure switches already bad??? HeloDown Problems & Fixes 4 09-08-2015 06:51 PM

2004, acura, acurs, car, circuit, code, control, crv, ecmpcm, error, honda, malfunctio, p0685, power, rdx, relay, tsx

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are On
Pingbacks are On
Refbacks are On


All times are GMT -5. The time now is 11:41 AM.

Honda and the Honda marquee are registered trademarks of the American Honda Motor Company, Inc. Neither American Honda Motor Company nor its subsidiaries or affiliates shall bear any responsibility for content, comments, or advertising. is not affiliated with American Honda Motor Company in any way. American Honda Motor Company does not sponsor, support, or endorse in any way. Copyright/trademark/sales mark infringements are not intended or implied.