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:

Battery Recharging [Mzr 2.0, Mzr 2.5]
Using GR8-1291: (See GR8-1291 INSTANT TRAINING MODULE (VIDEO) .) WARNING: Keep all flames away from the battery, otherwise evaporated gas from the battery fluid may catch fire and cause serious injury. 1. Remove the battery filler caps and check the water level. If necessary, add ...

Registering Your Vehicle in A Foreign Country (Except United States and Canada)
Registering your vehicle in a foreign country may be problematic depending on whether it meets the specific emission and safety standards of the country in which the vehicle will be driven. Consequently, your vehicle may require modifications at personal expense in order to meet the regulat ...

Rear Seat Belt Removal/Installation
CAUTION: The ELR (emergency locking retractor) has a spring that will unwind if the retractor cover is removed. The spring cannot be rewound by hand. If this occurs, the ELR will not work properly. Therefore, do not disassemble the retractor. 4SD 1. Remove the following part ...