FixVault

Code A034: Brake Switch Shorted

When brake pedal is applied, the brake switch closes. This causes voltage application from STOP fuse to the anti-lock brake controller and brakelights. To set Code A034, the following conditions must occur.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Verifies short still exists (brakelights on).
  2. Isolates short to battery in circuit No. 20 or brake switch.
  3. If Code A034 is consistent and brake switch and circuit are okay, anti-lock brake controller must be defective.
  4. Determines if code is intermittent.
NOTE: INTERMITTENTS  is located under DIAGNOSIS & TESTING.
Fig 1: Code A034 Schematic, Brake Switch Shorted
G91I11260Courtesy of GENERAL MOTORS CORP.
Fig 2: Code A034 Flow Chart, Brake Switch Shorted
G109855Courtesy of GENERAL MOTORS CORP.
Fig 3: Code A034 Flow Chart, Brake Switch Shorted
GB0022435