Test Description

WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

2. Tests that the PCM receives a cooling fan speed signal through the cooling fan speed signal circuit. If answer to question is Yes, ensure to refer to all Diagnostic Aids.
3. Tests for the proper operation of the clutch hall effect sensor.
4. Tests for the proper operation of the 5-volt reference circuit and of the low reference circuit of the cooling fan.

Fig 1: Diagnostic System Check - DTC P1481 (1 Of 2)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Diagnostic System Check - DTC P1481 (2 Of 2)

Courtesy of GENERAL MOTORS CORP.