Test Description

WARNING: This page is about a different car, the 2003 Cadillac CTS. 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. This step determines the proper diagnostic path for the DTC.
4. This step test for battery voltage at the rear axle sensor.
5. Test for an open in the rear axle sensor ground circuit.
6. Test for both a short to ground and a short to battery voltage.
7. Test for an open or high resistance between the rear axle sensor and the headlamp leveling control module that has the DTC present.

Fig 1: DTC B3420 (Steps 1 - 4)
Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC B3420 (Steps 5 - 14)
Courtesy of GENERAL MOTORS CORP.