General instructions

• The drive is provided by the test rig.
• During the test the gearbox must be in neutral on manual gearboxes or in position N on automatic gearboxes.
• Follow the instructions provided by the manufacturer of the brake test equipment when performing the test.

Note Electronic brake control systems are inoperative when the ignition is switched off.

Checking vehicles with front-wheel drive

• The brake test must be performed on a single-axle roller dynamometer.
• The test speed must not exceed 6 km/h. Otherwise the EDL control can activate the brakes if the rollers start at different points in time.
• The SEAT approved test stands meet these criteria.

Testing vehicles with four-wheel drive

Testing on a speed-controlled, counterrotating brake dynamometer for four-wheel drive vehicles

Note The brake test must be performed on a controlled contra-rotating single-axle roller dynamometer for four-wheel drive vehicles.

Contra-rotating means that the dynamometer rollers are driven forwards on one side and backwards on the opposite side.

The rollers drive the wheels of one axle in opposite directions to avoid transmitting torque to the other axle.

"Speed-controlled" means: The speed of the test rollers is controlled so that there is no difference in wheel speeds during the brake test.

This prevents any torque being transmitted along the drive train between the stationary wheels (which are off the set of rollers) and the rotating wheels on the rollers.

With brake tests, the measurement is always carried out on the wheel rotating in the driving direction. This is why two brake tests have to be carried out per axle.

Test speed must not exceed 6 km/h.

The SEAT approved test stands meet these criteria.

Testing without special equipment for four-wheel drive vehicles

Note If no test rig is available for four-wheel drive vehicles, the brake test can also be carried out on a standard single-axle roller dynamometer as follows:

• Drive vehicle forwards onto rollers.
• Switch off engine and wait for 2 seconds.
• Run braking test for front wheels.
• Start engine and wait for approx. 5 seconds until sufficient vacuum has built up.
• Move vehicle forwards until the rear wheels are on the rollers.
• Switch off engine and wait for 2 seconds.
• Run braking test for rear wheels.
• Start engine and wait for approx. 5 seconds until sufficient vacuum has built up.