FixVault
Home › Isuzu › 2007 › Ascender 4WD › Repair and Diagnosis › Accessories & Equipment › Memory Modules › Secondary And Configurable Customer Controls › Diagnostic Information and Procedures › Steering Wheel Controls Inoperative › Circuit/System Testing

Circuit/System Testing

IMPORTANT: It is recommended that Component Testing is performed before Circuit Testing when diagnosing steering wheel controls.
CAUTION: Refer to SIR Caution .
  1. Ignition OFF, disconnect the harness connector at the right steering wheel control switch.
  2. Ignition ON, test for 11.5-12.5 volts between the 12-volt reference circuit terminal 1 and ground.
    • If less than the specified value, test the 12-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
    • If greater than the specified value, test the 12-volt reference circuit for a short to voltage. If the circuit tests normal, replace the BCM.
  3. Test for 11.5-12.5 volts between the 12-volt reference circuit terminal 1 and the signal circuit terminal 6.
    • If less than the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
    • If greater than the specified value, test the signal circuit for a short to voltage.
  4. Install a 3A fused jumper wire at the 12-volt reference circuit terminal 1 and the 12-volt reference jumper terminal 2.
  5. Disconnect the harness connector at the left steering wheel control switch.
  6. Test for 11.5-12.5 volts between the 12-volt reference jumper terminal 1 and ground.
    • If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
    • If greater than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.
  7. Test for 11.5-12.5 volts between the 12-volt reference jumper terminal 1 and the signal circuit terminal 5.
    • If less than the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
  8. Disconnect the harness connector C1 at the BCM.
  9. Test for infinite resistance between the signal circuit terminal B8 and ground.
    • If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the BCM.
  10. If all circuits test normal, test or replace the switch.
About FixVault