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.

3. Tests for the proper operation of the circuit in the low voltage range.
4. Tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.
5. Tests for a short to voltage in the 5 volt reference circuit.
6. Tests for a high resistance or an open in the low reference circuit.

Fig 1: DTC B2620 - Diagnostic Chart (1 Of 2)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC B2620 - Diagnostic Chart (2 Of 2)

Courtesy of GENERAL MOTORS CORP.