FixVault

Circuit/System Testing

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT: When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected.
  • SDM
  • SDM wiring harness
  1. Ignition OFF, remove the underhood AIR BAG IGN fuse 39.
  2. Ignition ON, test for 9-16 V between the voltage supply side and ground.
    • If not within the specified range, refer to DTC B1370 .
  3. Ignition OFF, remove the SDM harness connector.
  4. Ignition OFF, test for less then 1 ohm between the ignition 1 voltage circuit terminal 32 and the underhood fuse block terminal G2 (X5).
    • If greater then the specified range, test the circuit for an open/high resistance.
  5. Ignition ON, test for less then 1 volt between the SDM harness connector ignition 1 voltage circuit terminal 32 and the underhood fuse block terminal G2 (X5).
    • If greater then the specified value, test the circuit for a short to voltage.
  6. If all circuits test normal, reconnect all connectors, replace fuse, clear all DTCs. If DTC B1370 stays current, replace the SDM.