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Home >> Cadillac >> 2002 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 93 (Engine Controls Self-Diagnostics) >> Diagnostic Tests >> DTC P0030: Ho2S Heater Control Circuit Sensor 1 >> Test Description
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Test Description

WARNING: This page is about a different car, the 2002 Pontiac Aztek and 2002 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers in the diagnostic procedures.

  1. 2

    Inspect the heater current with the engine at operating temperature, and allow time for the heater current to stabilize. The HO2S 1 heater current is initially higher until the sensor reaches full operating temperature.
  2. 4

    A DTC fail in this step verifies the problem is present with the HO2S 1 disconnected.