For 1990-2009 cars

1. Apply the parking brake.
2. Drain all of the reservoirs. Refer to Draining Reservoirs .
3. Start the engine and run the engine at a fast idle.
4. Verify that the low pressure tone alarm is on.

• | If the tone alarm is not on when first charging the system, test the brake warning system.

• | For diagnosis of the brake warning system, refer to Brake Warning Alarm Inoperative .

5. The low pressure tone alarm should turn off when the dual air pressure gauge indicates 470-510 kPa (68-74 psi).

• | If the tone alarm does not turn off, test the brake warning system.

• | For diagnosis of the brake warning system, refer to Brake Warning Alarm Always On .