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 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition ON, use a scan tool clear the current and history DTC.
  2. Determine which motor set the DTC by operating the motors listed below one at a time in both directions. Check for the DTC to set between each motor test.
    • Driver seat front vertical motor
    • Driver seat rear vertical motor
    • Driver seat horizontal motor
    • Driver seat horizontal lumbar motor
    • Driver seat vertical lumbar motor
    • Driver seat recline motor
    • Steering column telescope motor
    • Steering column tilt motor
  3. Clear the diagnostic trouble code.
  4. Ignition OFF, disconnect the harness connector at the appropriate seat, lumbar, or steering column motor listed below for which the DTC set.
    • Seat adjuster assembly X1
    • Seat recline motor X1
    • Lumbar horizontal motor X1
    • Lumbar vertical motor X2
    • Steering column telescope motor X1
    • Steering column tilt motor X1
  5. Ignition ON, operate the motor adjuster switch in both directions. DTC B1335 0B should not set.
    • If the DTC sets, test for a short to ground or a short between the appropriate control circuits listed below: If the circuits test normal, replace the MSM.
      • Front vertical motor terminal 2 and terminal 5
      • Rear vertical motor terminal 1 and terminal 4
      • Seat horizontal motor terminal 3 and terminal 6
      • Seat recline motor terminal A and terminal B
      • Lumbar vertical motor terminal A and terminal B
      • Lumbar horizontal motor terminal A and terminal B
      • Steering column telescope motor terminal A and terminal B
      • Steering column tilt motor terminal A and terminal B
  6. If all circuits test normal, test or replace the appropriate seat, lumbar or steering column motor assembly.
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When to See a Mechanic

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

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