GM Truck Club
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 2 of 2
  1. #1

    Default 2008 Suburban LTZ that has electrical issues

    I purchased a used 2008 Suburban LTZ with 70,xxx miles last year and have had nothing but trouble. Now I'm having issue with the electrical system.

    Here is what has happened:

    I was pulling a trailer and it started acting weird when I would put on the left turn signal. All of the electronics inside would shut down and then come back on.

    Then it started doing it just driving it down the road. When we got to where we were going it was completely dead. I giggle some wires and it came back to life.

    After a few weeks of it running just fine, it started up again. doing the same thing. Well this has been going on for some time and I have narrowed it down to one small connection on the ground cable going to the battery. It is 3 or 4 wire connection that is wrapped around the ground. It doesn't look like it has anything to do with the ground.

    I've taken it to a couple of different mechanics, but they haven't been able to duplicate the problem.

    I found another post on here from May 2011 where somebody else had the same problem, but the end results of what they did to fix it wasn't posted.


    1 Anyone seen this before?
    2 What in the world is the black plastic thingy on the negative battery cable?
    3 Anyone know where to find a wiring diagram for this thing?
    4. Does anybody know how to fix this?


  2. #2


    the black box on the negative cable is a stand alone regulated voltage control. Here is some info about it from one of the manufacturers site:

    The "Stand Alone Regulated Voltage Control" (SARVC) uses a "Generator Battery Control Module" to control the alternator set point. The other RVC systems, Generation III and Generation IV, use up to five different computers to operate the entire system and control the alternator regulator set point. There is a default voltage regulator set point built into the regulator. It is set at 13.8 volts. If the system fails at any point the regulator will default to the 13.8 volts and a code will be set.

    1995 Silverado 4x4
    6" BDS Suspension Lift-3" Body Lift-Add A Leaf in rear -Trailmaster SSV Shocks-Duel Steering Stabilizer Kit -AirAid Cold air intake-
    4.56 Gears with Detroit Auburn Locker-Pro-Comp Traction Bars with duel shocks-Aluminum Skid Plate Kit-38.5" x 16.5" Mickey Thompson Baja Claws-Constant Dropping fuel gauge

    2005 Yukon XL Jet Power Programmer, Bilstein Shocks, Bilstein rear springs, Helwig Anti-sway bars, EGR Window Visors, EGR Hood Shield, Denali Headlights, Headlight harness upgrade, GE NightHawk Bulbs, White Night Rear lighting system, Russell Braided SS brake lines, PowerStop Brake pads, PowerStop cross drilled and Slotted Rotors,
    2002 Silverado ext cab 2wd (Sold)
    2003 Yukon XL (Totaled)

Tags for this Thread

Posting Permissions

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