Chevrolet Sonic Repair Manual: Brake Pedal Travel Measurement and Inspection

Special Tools

CH-28662 Brake Pedal Effort Gauge

For equivalent regional tools, refer to Special Tools.

1. With the ignition OFF and the brakes cool, apply the brakes 3–5 times, or until the brake pedal becomes firm, in order to deplete the brake booster power reserve.


2. Install the CH-28662 gauge  (1), or equivalent, to the brake pedal (3).
3. Measure and record the distance (a) from the brake pedal (3) to the rim of the steering wheel (2). Note the points of measurement.


4. Apply and maintain a force of 445 N (100 lb) to the brake pedal, as indicated on the CH-28662 gauge  (1), or equivalent.
5. While maintaining 445 N (100 lb) of force to the brake pedal (3), measure and record the distance (b) from the same point on the brake pedal (3) to the same point on the rim of the steering wheel (2).
6. Release the brake pedal (3) and repeat steps 4 and 5 to obtain a second measurement. After obtaining a second measurement, proceed to step 7.
7. Average the first and second measurements recorded for the 2 applies of the brakes.
8. Subtract the initial unapplied distance (a), from the average applied distance (b) to obtain the brake pedal travel measurement (c).

   Specification

   
   Maximum brake pedal travel – measured with the ignition OFF, brake booster power assist depleted, and the brakes cool.