Test 1A - Checking For Diagnostic Trouble Codes

READING DIAGNOSTIC TROUBLE CODES
1. The diagnostic test procedure must begin with a thorough visual inspection of the ABS System. Inspect connectors and components for damage and/or proper connection. The brake lamp circuit also provides an input to the ABS System. If the brake lamps do not operate, they must be repaired.

2. Connect the DRB to the Diagnostic Connector.
^ If the DRB screen is blank, perform Test 18A. Test 18A - DRB Blank Screen

^ If there is an error message on the DRB screen, refer to the DRB user's guide.

3. Turn the ignition on. With the DRB, select ABS. If the DRB Shows "No Response", perform Test 17A. Test 17A - DRB "No Response" Message

4. With the DRB, select "Inputs/Outputs" and read the brake switch status. While pressing on the brake pedal, observe the DRB display.
^ If the brake switch status does not reflect the proper state of the brake pedal, perform Test 19A. Test 19A - Checking Brake Lamp Switch Input to CAB

^ Read the brake warning lamp status.

^ If the DRB does not reflect the state of the red Brake warning lamp, perform Test 31A. Test 31A - Red Brake Warning Lamp

^ Select Read DTC and record any trouble codes that appear. In some instances, the cause of one trouble code may trigger the setting of additional trouble codes.

^ If multiple trouble codes appear, a certain sequence of tests may be required. The beginning of each test will indicate whether another test should be performed first.

5. If no trouble codes are found perform Test VER2A. Verification Test VER-2A - (Road Test) - ABS