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 is switched to ON.

• When the ABS HU/CM is activated, the following malfunction detection is performed.

― The ABS and brake system warning lights illuminate for approx. 3 s when the ignition is switched to ON 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. 6 km/h {4 mph} or more to perform malfunction diagnosis again. Input/output signals are monitored for malfunction determination when the ignition is switched to ON.

• 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 has been switched OFF, 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
	DTC No.	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	Illuminated	Control disabled	Control disabled
	C0020:11
	C0020:13
	C0020:1C
	C0020:71
ABS wheel speed sensor	C0031:01	Illuminated	Not illuminated^*1	Control disabled	Control enabled^*2
	C0031:13
	C0034:01
	C0034:13
	C0037:01
	C0037:13
	C003A:01
	C003A:13
ABS wheel-speed sensor/ABS sensor rotor	C0031:23	Illuminated	Not illuminated^*1	Control disabled	Control enabled^*2
	C0034:23
	C0037:23
	C003A:23
	C0031:27
	C0034:27
	C0037:27
	C003A:27
	C0031:62	Illuminated	Illuminated	Control disabled	Control disabled
	C0034:62
	C0037:62
	C003A:62
Brake switch	C0040:13	Illuminated	Illuminated^*5	Control disabled	Control enabled^*3
Brake switch	C0040:64	Illuminated	Illuminated^*5	Control disabled	Control enabled^*3
Valve relay	C1A77:12	Illuminated	Illuminated	Control disabled	Control disabled
	C1A77:13
	C1A77:16
CAN line	U0001:88	Illuminated	Not illuminated	Control disabled	Control enabled^*3
	U0100:00	Illuminated	Not illuminated	Control disabled	Control enabled^*3
	U0214:00^*4	Not illuminated	Not illuminated	Control enabled	Control enabled
Module configuration	U2100:00	Illuminated	Not illuminated	Control disabled	Control enabled^*3
ABS unit mismatched installation	U3000:4A	Illuminated	Not illuminated	Control disabled	Control enabled^*3
ABS control (ABS HU/CM internal malfunction)	U3000:96	Illuminated	Illuminated	Control disabled	Control disabled
Power supply system	U3003:1C	Illuminated	Illuminated	Control disabled	Control disabled
	U3003:16	Illuminated	Illuminated	Control disabled	Control disabled
	U3003:17	Illuminated	Illuminated	Control disabled	Control disabled

*1 :Illuminates when one or two rear wheels have a malfunction.

*2 :Control which requires sensor data is inhibited. Moreover, control is inhibited when one or two rear wheels have a malfunction.

*3 :Control which requires sensor data is inhibited.

*4 :With advanced keyless entry and push button start system.

*5 :Vehicles without malfunction warning light. (Applied VIN (assumed): GH1***429761—,GH1***442043—,GH10**206766—,GH10**210449—,GH****210421—, GH1***442043—)