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:

Clutch Fluid Replacement/Air Bleeding [C66 M R]
CAUTION: Do not allow clutch fluid get on a painted surface. Clutch fluid contains properties which can dissolve the paint. If clutch fluid gets on a painted surface, wash it off with water immediately and wipe the area off completely. Do not mix different types of clutch fluid ...

Front Stabilizer Control Link Inspection
1. Remove the front stabilizer control link from the vehicle.. (See FRONT STABILIZER REMOVAL/INSTALLATION [MZR 2.3 DISI Turbo] 2. Inspect for bending or damage. If there is any malfunction, replace the stabilizer control link. 3. Rotate the ball joint stud 10 times and shake it side to side ...

Back Up Light Switch Removal/Installation [G66 M R]
1. Remove the battery cover.. 2. Disconnect the negative battery cable. 3. Remove the battery component. (ex: battery, battery tray and PCM component). 4. Remove the aerodynamic under cover No.2.. 5. Drain the oil from the transaxle.. 6. Disconnect the back-up light switch connector and r ...