Battery drain issue

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by Coneklr, Aug 31, 2009.

  1. RayVoy

    RayVoy Epic Member 5+ Years 5000 Posts

    Going to depend upon how many lights come on when you open the door. Other things "wake up" as well.
    One 10 watt lamp at battery voltage is going to draw 0.8 amps.

    Pull the fuse for the interior lights and see if there is still a draw when the door is opened.
  2. j cat

    j cat Epic Member 5+ Years 1000 Posts

    your .5 AMP draw is too high. should be below .25AMP or lower after about 15min.

    with a 12volt system each light bulb will draw a good amount of amps. a 12 WATT bulb will draw 1 AMP. when you open the door the interior lamps will draw a few amps.
  3. COACH

    COACH New Member

    went a chevy man claimed he had never heard of a gauge cluster module...where is it located....oh, by the way,they wanted to do a leak test for a $100.00
  4. j cat

    j cat Epic Member 5+ Years 1000 Posts

    the gauge cluster has an electronic module on it. the dealership would change the dash cluster. now there is no diagrams available with this . GM top secret !
  5. COACH

    COACH New Member

    thanks...the guy who redid my cluster had not heard of it
  6. Kaufmankdk

    Kaufmankdk New Member


    Here is my .2 Cents worth.

    And this thread is all but dead, but I have learned much from these Forums and this “Battery drain search”.

    First off, I am an Electrician with over 32 years of experience. “Yes, useless fact”.

    And Auto Electric is another animal, but that said. The more you work at it the better you get right!

    1) Using a D.C. Amprobe on the positive Cable I pulled the Fuses one at a time, at first I noticed no change, but with a little amount of time there will be change.

    2) This is where the cooler of beer and a friend come into play.

    3) Dust and any Liquid is not good, Tracking can and will occur. Clean and dry is best.

    4) Next, while pulling each fuse to search for the drain I used a New “Stainless Steel Tooth Brush” to clean each of the Fuse Tabs.

    5) I don’t mean to say REEF on them until the silver is removed; this in itself yielded great results. Oh starting at about 2.2 amps draw and down to .5 Amps and now down to .3 Amps

    6) During the search please don’t overlook the obvious like I did, the beer was instrumental in this equation. Doors, Glove Box and The last “Hood Light” that was not even lit. “Not working”

    7) So, it’s o.k. for the doors and glove box and the hood to be open as long as you are accounting for each of them.

    8) Clean and dry is the take away from all of this. And the finally was the “hood light fixture” has a mechanical Iron Pivot switch. Unplug the fixture to check for drain even if the light is not on.

    9) Hi resistance is Not good ever, any hi resistance will cause or simulate Load.

    10) The under hood lamp fixture was a mess; I might still have to replace the fixture. Years of bouncing “mechanical Iron Pivot switch” and probably will not hurt to go LED on all of the lamps anyway.

    11) I have a DC Amprobe. VOM in line of the ground works as well. Plenty of good information here.

    12) Thanks to all that provide support to U-Tube and The Forums, We all benefit from this.
  7. Kaufmankdk

    Kaufmankdk New Member

    Opdate: I eventually tracked my problem down to a "headlight / dome light switch". problem solved.
    It was intermittent and I chased it for the past 4 years.
    RayVoy likes this.
  8. j cat

    j cat Epic Member 5+ Years 1000 Posts

    the hood light is disconnected on all my vehicles from day one. on my sedan the trunk as well. many have had these type switches fail this way. the under hood/trunk lights should have mechanical switches when you need the light switch it on.
    xPosTech and squatchy like this.
  9. jimmyfan

    jimmyfan New Member

    99 GMC early body style 5.7L K3500
    Hi guys,
    This is my first post, I've seen some great question and even better answers I have an ex military 4WD Military Police truck. I added power mirrors, locks, and windows and a cross body harness 10 years ago.
    Now it has a parasitic drain. The book says any thing over a 50 milli amp draw is a problem, mine is a 90 milli amp draw., I put a scissor type disconnect in the negative battery cable (got tired of replacing dead batteries) I pulled the fuse for the EVO Passlock Module (electronic variable oriface ) most of the drain went away. However EVO module has its tentacles into just about everything, ((strng) ie. security ie. theft deterrent system including the key lock sensor, Passlock sensor signal, two tamper sensors, tamper resistor, security lamp and non security/theft things like a 5v reference, 12v reference, variable power steering, transfer case controls, instrument cluster gauges, Serial Data Class 2, i.e Data Link Connector i.e. OBD 11 connector. steering wheel sensor, shock sensor, ignition, and a ground etc.etc.etc.)
    The EVO module is expensive! How do i test the rest of these things listed above or rule out the EVO module?
    Because if the problem is not the EVO module I just wasted big bucks on a used
    electric module that i can't return!

    Thanks, I hope that one of you has had to fix this problem,.... on someone elses vehicle......for lots of money!
  10. RayVoy

    RayVoy Epic Member 5+ Years 5000 Posts

    The biggest problem with todays vehicles, is the LAN. Not actually the LAN, just the fact that there is a LAN. When it works, it is an awesome addition; when it doesn't, it causes a lot of grief. An example is RAP (retained accessory power) a series software commands that leaves some "switched power" accessories turned on after the key is removed (this is the system that leaves the radio on for 10 mins after the key is removed).

    Here's the problem, back in the day, the ignition key controlled the voltage to all of these accessories, remove the key, the voltage is removed the accessory is turned off.

    Today, nothing is turned off with the key, well maybe the engine; today, the accessories are always "hot". Commands are sent on the LAN to put these accessories "to sleep". When they sleep, very low current draw. The problem is, they don't always go to sleep. Then there is a high current draw.

    If they all stay on, suspect the BCM, if it is only one that stays on and the others go into sleep mode, of course, suspect the module that doesn't sleep.
    Like all other circuits, it's the intermittent one that causes the bare spots on the top of your head.

    Of course, we also have all of the usual circuits that cause battery drain, like lights, etc..

Share This Page

Newest Gallery Photos