Clear OBD (check engine) codes by disconnect battery



ChryslerMiniVan.net is the premier Chrysler Minivan Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 8 of 8

Thread: Clear OBD (check engine) codes by disconnect battery

  1. #1
    Join Date
    Sep 2008
    Location
    Lockport, IL
    Posts
    3
    Thanks
    0
    Thanked 0 Times in 0 Posts


    Clear OBD (check engine) codes by disconnect battery

    A new member here. Sorry if I'm beating a dead horse here.

    I have seen several mentions of disconnecting your negative battery terminal for a time period to clear your OBD codes.
    I live in Illinois and need to pass a EPA test. They now check for OBD's. Will the disconnect clear everything ? Or at least enough to pass ??

    Comments !

    Thanks to all in advance.

  2. Remove Advertisements
    Chrysler Minivan Forums
    Advertisements
     

  3. #2
    Join Date
    Dec 2004
    Location
    Virginia
    Posts
    4,021
    Country: Users Country Flag
    Thanks
    83
    Thanked 60 Times in 42 Posts


    It depends a great deal on what problems there are. Some problems will cause the Check Engine Light to turn on right away, others take some time. So depending on the problem, the light may turn on, on the way to the inspection station. In any case, the OBD will show that the battery was disconnected within the past 50 starts or so.
    Michael
    Centreville, VA
    Currently driving:
    2005 Dodge Grand Caravan SXT, 99K mi.
    Former owner of:
    1988 Dodge Caravan SE, 2.5L I4 (1988-1995, 99K mi); 1995 Plymouth Grand Voyager SE "Rallye", 3.3L (1995-2004, 169K mi); 2003 Grand Caravan Sport, 3.8L, (2004-2008, 106K mi), 2008 Nissan Quest, (2008-2010, 25K mi)

    Other vehicles:
    2008 Lexus RX400h (Dark Gray), 65K mi; 2005 Hyundai Elantra GT (Blue), 65K mi

  4. #3
    Join Date
    Jan 2008
    Location
    Nova Scotia, Canada
    Posts
    13,921
    Country: Users Country Flag
    Thanks
    680
    Thanked 1,244 Times in 1,020 Posts


    Quote Originally Posted by Hckynut56 View Post
    A new member here. Sorry if I'm beating a dead horse here.

    I have seen several mentions of disconnecting your negative battery terminal for a time period to clear your OBD codes.
    I live in Illinois and need to pass a EPA test. They now check for OBD's. Will the disconnect clear everything ? Or at least enough to pass ??

    Comments !

    Thanks to all in advance.
    X2 (Same as response to EGR Valve Post)
    Disconnecting the battery (say for 10 minutes) will clear the codes if they are no longer applicable such as glitches or the problem was remedied (replaced upstream oxygen sensor for example).
    If the EGR Valve is indeed faulty, the code will reappear and the check engine light may come on. After a battery disconnection, a code P1684 ("battery disconnected .......") will show up if you access the computer (using key dance method) and will disappear after 50 restarts. Otherwise you will get "donE" if no detectable faults are present.
    2007 GC SXT - Magnesium - S&G - 3.8L - 115,600 kms
    2002 GC Sport - Stone White - 3.3L - 314,240 kms
    2003 Jeep TJ Sport - 4.0L - 246,430 kms

  5. #4
    Join Date
    Dec 2007
    Location
    Virginia
    Posts
    259
    Thanks
    0
    Thanked 7 Times in 5 Posts


    Quote Originally Posted by mmahamm View Post
    It depends a great deal on what problems there are. Some problems will cause the Check Engine Light to turn on right away, others take some time. So depending on the problem, the light may turn on, on the way to the inspection station. In any case, the OBD will show that the battery was disconnected within the past 50 starts or so.
    I've disconnected my battery on several occasions over the past few years, including recently (when working on heat/AC issues under the dash) and my check engine light never did turn on (even the radio station presets were still good). The battery was typically disconnected for at least 30 minutes, often much longer (hours). However, I never did the key dance trick to see if of any codes were present (such as the one referring to the battery disconnect in the last 50 starts). It may have been present but the Check Engine light never activated so I didn't check.

    Oddly enough, I once had a check Engine Light condition and the keydance code was the "battery disconnected" code (1684?). But that occurred nowhere near anytime that I had disconnected the battery.

    Just FYI.
    Dave
    • 2003 DGC SE 3.3L - 248K miles and still strong
    • 2003 Nissan Frontier 2.4L - 186K miles
    • 2005 Ford Focus - 158K miles
    • 2008 Honda Civic - 90K miles

  6. #5
    Join Date
    Jan 2008
    Location
    Nova Scotia, Canada
    Posts
    13,921
    Country: Users Country Flag
    Thanks
    680
    Thanked 1,244 Times in 1,020 Posts


    Quote Originally Posted by DaveKG55 View Post
    I've disconnected my battery on several occasions over the past few years, including recently (when working on heat/AC issues under the dash) and my check engine light never did turn on (even the radio station presets were still good). The battery was typically disconnected for at least 30 minutes, often much longer (hours). However, I never did the key dance trick to see if of any codes were present (such as the one referring to the battery disconnect in the last 50 starts). It may have been present but the Check Engine light never activated so I didn't check.

    Oddly enough, I once had a check Engine Light condition and the keydance code was the "battery disconnected" code (1684?). But that occurred nowhere near anytime that I had disconnected the battery.

    Just FYI.
    I know what you mean. The "check engine" light doesn't come on for P1684 normally. That's okay.
    If you check for fault codes (key dance method) and find P1684 showing up, there likely has been a power disruption of some sort, maybe even a loose battery connection, or a "quick learn" (if one was performed recently) that triggered it. The fault, really, is power to the TCM has been interrupted. For possible reasons, check this site.
    http://dodge.justanswer.com/question...3-t-c-3-8-know
    2007 GC SXT - Magnesium - S&G - 3.8L - 115,600 kms
    2002 GC Sport - Stone White - 3.3L - 314,240 kms
    2003 Jeep TJ Sport - 4.0L - 246,430 kms

  7. #6
    Join Date
    Oct 2008
    Location
    pennsylvania
    Posts
    19
    Thanks
    0
    Thanked 0 Times in 0 Posts


    unhooking your battery will clear your computer's memory of stored codes. your computer tests different systems on your car on a preset "drive cycle"- each test runs when different driving conditions are met. some tests run as soon as the key is turned on, some take several key cycles and cold soak periods (car sitting overnight). the results of these tests are stored and processed in your car's pcm (Powertrain Control Module aka the computer)these results are what the pcm uses to determine whether or not to illuminate the check engine light (aka MIL or idiot light or SES light- all the same) when you take your car in for emissions, the computer the shop uses checks your pcm for readiness monitors (the pcm's list of completed or not tests) the emissions test will only run if all of your monitors are set, so by unhooking the battery your car will show up as "not ready for testing" and the garage will tell you that you unhooked your battery and send you on your way to come back in a week or so. the best bet is that Autozone does free scan tests, there are also some others that do this too. they will even try to sell you the part they think you need!

  8. #7
    Join Date
    Aug 2008
    Posts
    296
    Thanks
    1
    Thanked 3 Times in 2 Posts


    If you want to erase the code before go to emission test,you should buy the DRB ll scan at Sear,it's about $80,after erase the code you can return it if you want to,I did mine before.
    good luck

  9. #8
    Join Date
    Sep 2008
    Location
    Canada
    Posts
    405
    Thanks
    0
    Thanked 0 Times in 0 Posts


    It depends on how thorough the emission test is.
    It differs by state.
    In some states as long at the MIL isn't illuminated but working (bulb check) your good.

    Others will test the system and see if it passed all the self tests. Clearing codes or disconnecting the battery just before testing will automatically fail.
    And finally some states will test (sniff) the tail pipe and measure the harmfull emissions. If your levels are too high...You fail
    2003 GRAND CARAVAN SPORT
    1997 RAM 1500 SPORT 4x4
    2003 ALERO

+ Reply to Thread

Quick Reply Quick Reply

Similar Threads

  1. Check engine light codes
    By Miron in forum 4th. Generation Chrysler Minivans: 2001-2007
    Replies: 12
    Last Post: 06-17-2009, 10:44 PM
  2. Check engine codes
    By 97_grandvoyager_uk in forum 3rd Generation Chrysler Minivans: 1996-2000
    Replies: 9
    Last Post: 06-01-2008, 10:20 PM
  3. check engine codes
    By patrick30 in forum 4th. Generation Chrysler Minivans: 2001-2007
    Replies: 2
    Last Post: 05-29-2008, 08:59 AM
  4. Ignition Key Check for Check Engine Codes
    By bluebgone in forum 4th. Generation Chrysler Minivans: 2001-2007
    Replies: 1
    Last Post: 12-28-2007, 07:28 PM

Bookmarks

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts