Circuit/System Testing

2008 Chevrolet Chevy Express G2500, Van Cargo, 6.6 6SECTION Circuit/System Testing
WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT: Diagnose any antilock brake system (ABS) related DTCs before performing this diagnostic.
  1. Ignition OFF, disconnect the X4 harness connector at the radio.
  2. Ignition ON, operate the vehicle drive wheels at 5 mph. Test for 3-7 Hertz between the VSS circuit terminal 5 and ground.
    • If not within the specified range, test the VSS circuit for an open, high resistance, short to ground or short to voltage. If the circuit tests normal replace the EBCM.
  3. If the circuit tests normal, replace the radio.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.