ON-BOARD DIAGNOSTIC SYSTEM FUNCTION [ABS]

id0402a7182100


Malfunction detection function

•  The malfunction detection function detects and displays malfunctions in the input/output signal system of the ABS HU/CM when the ignition switch is turned to the ON position.
•  When the ABS HU/CM is activated, the following malfunction detection is performed.
―  The ABS and brake system warning lights illuminate for approx. 3.0 s when the ignition switch is turned to the ON position to inspect for open circuits in the lights.At the same time, the fail-safe relay is operated, and the input/output signals of each part are monitored for malfunction diagnosis.After initial acceleration, the pump motor is operated while the vehicle speed is approx. 10 km/h {6.2 mph} or more to perform malfunction diagnosis again. Input/output signals are monitored for malfunction determination when the ignition switch is turned to the ON position.
•  If the above malfunctions are detected, the corresponding lights are illuminated to alert the driver. DTCs can be output through the CAN_H and CAN_L of the DLC-2 using the external tester communication function. At the same time, malfunction detection results are sent to the memory and fail-safe functions.

Memory function

•  The memory function stores DTCs of malfunctions in input/output signal systems. With this function, once a DTC is stored it is not cleared after the ignition switch has been turned off (LOCK position), even if the malfunctioning signal system has returned to normal.
•  Since the ABS HU/CM has a built-in non-volatile memory, DTCs are not cleared even if the battery is removed. Therefore, it is necessary to clear the memory after performing repairs.Refer to the Workshop Manual for the DTC clearing procedure.

Fail-safe function

•  When the malfunction detection function determines a malfunction, each light illuminates to advise the driver.At this time, the fail-safe function controls the ABS and EBD as indicated in the fail-safe function table.
Warning
•  If EBD control is prohibited the rear wheels could lock-up before the front wheels.If this occurs, the vehicle could yaw and become unstable. Therefore always inspect the system immediately if EBD control is prohibited.

Fail-safe Function Malfunction Contents

Malfunction location

DTC No.

Fail-safe function

Warning light illumination status

Control status

Mazda Modular Diagnostic System (M-MDS) display

ABS warning light

Brake system warning light (parking brake released)

ABS control

EBD control
ABS HU/CM internal malfunction (LF inlet solenoid)
C0010:01
Illuminated
Illuminated
Control disabled
Control disabled
ABS HU/CM internal malfunction (LF outlet solenoid)
C0011:01
ABS HU/CM internal malfunction (RF inlet solenoid)
C0014:01
ABS HU/CM internal malfunction (RF outlet solenoid)
C0015:01
ABS HU/CM internal malfunction (LR inlet solenoid)
C0018:01
ABS HU/CM internal malfunction (LR outlet solenoid)
C0019:01
ABS HU/CM internal malfunction (RR inlet solenoid)
C001C:01
ABS HU/CM internal malfunction (RR outlet solenoid)
C001D:01
Pump motor, motor relay
C0020:01
Illuminated
Not illuminated
Control disabled
Control enabled
C0020:1C
C0020:71
ABS sensor rotor
C0030:07
Illuminated
Not illuminated*1
Control disabled
Control enabled*2
C0033:07
C0036:07
C0039:07
ABS wheel
speed sensor
C0031:01
Illuminated
Not illuminated*1
Control disabled
Control enabled*2
C0034:01
C0037:01
C003A:01
ABS wheel-speed sensor/ABS sensor rotor
C0031:07
Illuminated
Not illuminated*1
Control disabled
Control enabled*2
C0034:07
C0037:07
C003A:07
Brake switch
C0040:64
Not illuminated
Not illuminated
Control enabled
Control enabled
CAN line
U0001:88
Not illuminated
Not illuminated
Control enabled
Control enabled
U0100:00
Not illuminated
Not illuminated
Control enabled
Control enabled
U0155:00
Illuminated
Not illuminated
Control disabled
Control enabled
U2101:00
Illuminated
Not illuminated
Control disabled
Control enabled
ABS HU/CM (internal malfunction)
U3000:47
Illuminated
Illuminated
Control disabled
Control disabled
U3000:48
U3000:49
Power supply system
U3003:16
Illuminated
Not illuminated*3
Control disabled
Control enabled*3
Illuminated*4
Control disabled*4
U3003:17
Illuminated
Illuminated
Control disabled
Control disabled

*1  :Illuminates when two wheels or more have a malfunction.
*2  :Control disabled when two wheels or more have a malfunction.
*3  :Detected if condition of 9.4—10.0 V or less continues for 210 ms or more.
*4  :Detected if condition of 7.55—8.45 V or less continues for 30 s or more.