Mazda MX-5 Miata / Grand Touring. Manual — part 20

2008 BRAKES

Antilock Brake System - MX-5 Miata

ABS LOCATION INDEX

Fig. 1: Identifying Location Of ABS Components
Courtesy of MAZDA MOTORS CORP.

ABS SYSTEM WIRING DIAGRAM

2008 Mazda MX-5 Miata Grand Touring

2008 BRAKES Antilock Brake System - MX-5 Miata

2008 Mazda MX-5 Miata Grand Touring

2008 BRAKES Antilock Brake System - MX-5 Miata

Fig. 2: ABS System Wiring Diagram
Courtesy of MAZDA MOTORS CORP.

ABS SYSTEM INSPECTION

ABS HYDRAULIC UNIT ON-VEHICLE INSPECTION

Preparation

1. Verify that battery is fully charged.

2. Turn the ignition switch to the ON position and verify that the ABS warning light goes out after approx.

2008 Mazda MX-5 Miata Grand Touring

2008 BRAKES Antilock Brake System - MX-5 Miata

3s .

3. Turn the ignition switch off.

4. Jack up the vehicle and support it evenly on safety stands.

5. Shift to neutral.

6. Release the parking brake.

7. Verify that all four wheels rotate.

8. Rotate the wheels by hand, and verify there is no brake drag.



If there is any brake drag, perform regular brake inspection.



If there is no brake drag, perform ABS HU/CM operation inspection.

Operation Inspection

1. Perform "Preparation".

2. Connect the M-MDS or equivalent to the DLC-2.

3. Set up an active command mode inspection according to the combination of commands below.

Fig. 3: Locating DLC-2 Connector
Courtesy of MAZDA MOTORS CORP.

ACTIVE COMMAND MODE INSPECTION REFERENCE TABLE

Operation

Command name

Command

2008 Mazda MX-5 Miata Grand Touring

2008 BRAKES Antilock Brake System - MX-5 Miata

The ACTIVE COMMAND MODE INSPECTION REFERENCE TABLE above shows an example
of a right front wheel inspection.

4. Send the command while depressing the brake pedal and attempting to rotate the wheel being inspected.

5. Performing the inspection above determines the following:



The ABS HU/CM brake lines are normal.



The ABS HU/CM hydraulic system is not significantly abnormal (including inside ABS HU/CM).



The ABS HU/CM internal electrical parts (solenoid, motor and other parts) are normal.



The ABS HU/CM output system wiring harnesses (solenoid valve, relay system) are normal.



However, the following items cannot be verified.



Malfunction of ABS HU/CM input system wiring harnesses and parts



Extremely small leaks in the ABS HU/CM internal hydraulic system



Malfunction with intermittent occurrence of the above items

ABS HU/CM REMOVAL/INSTALLATION

1. Perform ABS configuration. (See ABS CONFIGURATION .)

2. Remove in the order indicated in Fig. 4 .

3. Install in the reverse order of removal.

condition

PMP_MOTOR

RF_OUTLET

RF_INLET

transmission type

Brake pressure

retention

OFF

OFF

ON

Manual

Brake pressure

reduction

ON

ON

ON

CAUTION:



To protect the ABS HU/CM, the solenoid valve and the pump
motor used during active command mode stay on for only 10 s
or less each time they are switched on.

NOTE:



When working with two people, one should press on the brake pedal,
and the other should attempt to rotate the wheel being inspected.

CAUTION:



When replacing the DSC HU/CM with a new one, configuration
procedure must be performed before removing the DSC HU/CM. If
configuration is not completed before removing the DSC HU/CM, DTC
B2477 will be detected.



The internal parts of the ABS HU/CM could be damaged if dropped.
Be careful not to drop the ABS HU/CM. Replace the ABS HU/CM if it
is subjected to an impact.

2008 Mazda MX-5 Miata Grand Touring

2008 BRAKES Antilock Brake System - MX-5 Miata