Mazda 3 Service Manual: ABS HU/CM Inspection

Mazda 3 Service Manual / Brakes / Brake Control, Vehicle Dynamics / ABS / ABS HU/CM Inspection

1. Disconnect the ABS HU/CM connector..

2. Connect the negative battery cable..

3. Attach the tester lead to the ABS HU/CM wiring harness-side connector and inspect the voltage, continuity, or resistance according to the standard (reference value) in the table below.

Standard (reference)


Terminal	Signal name	Connected to	Measured item	Measured terminal (measurement condition)	Standard	Inspection item(s)
A	−	−	−	−	−	−
B	Ground	Ground point	Continuity	B—ground point	Continuity detected	Wiring harness (B—ground point)
C	RR wheel-speed (-)	RR ABS wheel-speed sensor	Continuity	C–RR ABS wheel-speed sensor connector terminal B	Continuity detected	Wiring harness (C–RR ABS wheel-speed sensor connector terminal B)
D	−	−	−	−	−	−
E	RR wheel-speed (+)	RR ABS wheel-speed sensor	Continuity	E–RR ABS wheel-speed sensor connector terminal A	Continuity detected	Wiring harness (E–RR ABS wheel-speed sensor connector terminal A)
F	−	−	−	−	−	−
G	−	−	−	−	−	−
H	CAN_H	DLC-2 (CAN_H)	This terminal is used for communication and cannot be used for malfunction determination during terminal voltage inspection.Perform a DTC inspection.
I	LF wheel-speed (+)	LF ABS wheel speed sensor	Continuity	I–LF ABS wheel-speed sensor connector terminal A	Continuity detected	Wiring harness (I–LF ABS wheel-speed sensor connector terminal A)
J	−	−	−	−	−	−
K	LF wheel-speed (-)	ABS wheel-speed sensor (LF)	Continuity	K–LF ABS wheel-speed sensor connector terminal B	Continuity detected	Wiring harness (K–LF ABS wheel-speed sensor connector terminal B)
L	CAN_L	DLC-2 (CAN_L)	This terminal is used for communication and cannot be used for malfunction determination during terminal voltage inspection.Perform a DTC inspection.
M	−	−	−	−	−	−
N	Power supply (System)	Ignition switch or IG1 relay	Voltage	Switch the ignition to ON	B+	Wiring harness (N—ignition switch or IG1 relay)
N	Power supply (System)	Ignition switch or IG1 relay	Voltage	Switch the ignition to off	1 V or less	Wiring harness (N—ignition switch or IG1 relay)
O	RF wheel-speed (-)	RF ABS wheel-speed sensor	Continuity	O–RF ABS wheel-speed sensor terminal B	Continuity detected	Wiring harness (O–RF ABS wheel-speed sensor connector terminal B)
P	−	−	−	−	−	−
Q	RF wheel-speed (+)	RF ABS wheel-speed sensor	Continuity	Q–RF ABS wheel-speed sensor terminal A	Continuity detected	Wiring harness (Q–RF ABS wheel-speed sensor connector terminal A)
R	−	−	−	−	−	−
S	−	−	−	−	−	−
T	−	−	−	−	−	−
U	LR wheel-speed (+)	LR ABS wheel-speed sensor	Continuity	U–LR ABS wheel-speed sensor connector terminal A	Continuity detected	Wiring harness (U–LR ABS wheel-speed sensor connector terminal A)
V	−	−	−	−	−	−
W	LR wheel-speed (-)	LR ABS wheel-speed sensor	Continuity	W–LR ABS wheel-speed sensor connector terminal B	Continuity detected	Wiring harness (W–LR ABS wheel-speed sensor connector terminal B)
X	−	−	−	−	−	−
Y	Power supply (Solenoid operation, ABS motor operation)	Battery	Voltage	Under any condition	B+	Wiring harness (Y–battery)
Z	−	−	−	−	−	−

ABS

...

ABS HU/CM Removal/Installation

WARNING: If the ABS HU/CM configuration is not completed, it could result in an unexpected accident due to the ABS being inoperative. If the ABS HU/CM or ABS CM is replaced, always use t ...

Other materials:

Rear Coil Spring Removal/Installation
1. Disconnect the auto leveling sensor lower side. (Vehicles with AFS). 2. Remove in the order indicated in the table. 3. Install in the reverse order of removal. 4. Inspect the wheel alignment and adjust it if necessary.. 1 Rear stabilizer control link upper nut ...

Ventilator Grille Removal/Installation
Side Ventilator grille 1. Through the wiring harness into the position shown in the figure, remove the side ventilator grille in the direction of arrow. 2. When installing the side ventilator grille, push it for the dashboard. Center Ventilator grille 1. Disconnect the negative battery c ...

M Position Switch Inspection [FS5 A EL]
1. Perform the following procedures. a. Remove the battery cover.. b. Disconnect the negative battery cable. c. Remove the console.. d. Disconnect the selector lever component connector. 2. Inspect the continuity between the selector lever component terminals A and H. If ...