GM Service Manual Online
For 1990-2009 cars only

Video Display is Poor or Blank

Schematic Reference: Video System Schematics

Connector End View Reference: Entertainment Connector End Views

Important: This diagnostic applies to the dual screen Platinum ULT Video Entertainment System only. For this symptom on the regular production C/K 800 vehicle, replace the digital video disc (DVD) player. Refer to Video Disc Player Replacement

Diagnostic System Check - Entertainment System

Always perform the Diagnostic System Check before proceeding with these diagnostic procedures. Refer to Diagnostic System Check - Vehicle in Vehicle DTC Information .

Important: 

   •  The following information lists the most probable cause of the concern to the least probable cause followed by the appropriate test for that condition. If the list leads to the replacement of a component, always inspect for a poor connection before proceeding with the replacement. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in wiring Systems.
   •  The causes of a poor display can be further isolated by knowing the operation of the wireless headphones and whether the screen display controls attempt to work. Meaning that if you try to change a display characteristic of the screen, does the user get visual feed back that a change was attempted? If the screen gives a visual feedback that a change was attempted, this is called screen controls work.

Both Displays are Blank, Screen Controls Work, Headphone Audio Works

  1. Ground circuit between the splitter box and the DVD player shorted to battery positive voltage--Test the ground circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  2. DVD video signal (+) between the splitter box and the DVD player open or shorted to ground or shorted to battery positive--Test the DVD video signal (+) for an open or short to ground or short to battery positive. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  3. DVD video signal (-) between the splitter box and the DVD player open--Test the DVD video signal (-) for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  4. Inoperative splitter box--Replace the splitter box.

Both Displays are Blank, Screen Controls Inoperative, Headphone Audio Inoperative

  1. Accessory voltage circuit between the splitter box and the DVD player open or shorted to ground--Test the accessory voltage circuit for an open or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  2. Battery positive voltage circuit between the splitter box and the DVD player open--Test the battery positive voltage circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  3. Audio common circuit between the splitter box and the DVD player shorted to battery positive--Test the audio common circuit for a short or battery positive. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  4. DVD video signal (-) between the splitter box and the DVD player shorted to ground or shorted to battery positive--Test the DVD video signal (-) for a short to ground or a short to battery positive. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  5. Video screen backlight supply voltage circuit between the splitter box and the DVD player shorted to ground--Test the video screen backlight supply voltage circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  6. Inoperative splitter box--Replace the splitter box.

Both Displays are Blank, Screen Controls Inoperative, Headphone Audio Works

  1. Video screen backlight ground circuit between the splitter box and the DVD player open or shorted to battery positive--Test the video screen backlight ground circuit for an open or short to battery positive. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  2. DVD serial data circuit between the splitter box and the DVD player open--Test the DVD serial data circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  3. Video screen backlight supply voltage circuit between the splitter box and the DVD player open--Test the video screen backlight supply voltage circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  4. Inoperative splitter box--Replace the splitter box.

Front Display Blank, Screen Controls Inoperative

  1. Video screen backlight ground circuit between the splitter box and the front display open--Test the video screen backlight ground circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems
  2. Inoperative splitter box--Replace the splitter box.

Front Display Blank, Screen Controls Work, Headphone Audio Inoperative

  1. Battery positive voltage circuit between the splitter box and the front display open--Test the battery positive voltage circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems
  2. Inoperative splitter box--Replace the splitter box.

Front Display Blank, Screen Controls Work, Headphone Audio Works

  1. DVD signal (+) circuit between the splitter box and the front display open--Test the DVD signal (+) circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems
  2. DVD serial data circuit between the splitter box and the front display open--Test the DVD serial data circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  3. Video screen backlight supply voltage circuit between the splitter box and the front display open--Test the video screen backlight supply voltage circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
  4. Inoperative splitter box--Replace the splitter box.