DSC HU/Cm Inspection

Disconnect the DSC HU/CM connector. (See DSC HU/CM REMOVAL/INSTALLATION .)
Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)

Attach the tester lead to the DSC HU/CM wiring harness-side connector and inspect voltage, continuity, or resistance according to the standard (reference) on the table.

If not specified, replace the DSC HU/CM. (See DSC HU/CM REMOVAL/INSTALLATION .)

Standard (Reference)

Fig 1: DSC HU/CM Connector Terminals

Courtesy of MAZDA MOTORS CORP.

Terminal	Signal name	Connected to	Measured item	Measured terminal (measurement condition)	Standard	Inspection item(s)
A	Power supply	Battery	Voltage	Under any condition	B+	Wiring harness (A- battery)
A	(solenoid operation)	Battery	Voltage	Under any condition	B+	Wiring harness (A- battery)
B	Power supply	Battery	Voltage	Under any condition	B+	Wiring harness (B- battery)
B	(motor operation)	Battery	Voltage	Under any condition	B+	Wiring harness (B- battery)
C	CAN_H	CAN module	This terminal is used for communication and cannot be used for malfunction determination during terminal voltage inspection. Perform a DTC inspection.
D	CAN_L	CAN module	This terminal is used for communication and cannot be used for malfunction determination during terminal voltage inspection. Perform a DTC inspection.
E	-	-	-	-	-	-
F	-	-	-	-	-	-
G	-	-	-	-	-	-
H	-	-	-	-	-	-
I	Power supply (system)	Ignition switch	Voltage	Ignition switched ON (engine off).	B+	Wiring harness (I- ignition switch)
I	Power supply (system)	Ignition switch	Voltage	Switch the ignition OFF.	1 V or less	Wiring harness (I- ignition switch)
J	RF wheel-speed (+)	RF ABS wheel-speed sensor	Continuity	J-RF ABS wheel-speed sensor terminal A	Continuity detected	Wiring harness (J-RF ABS wheel-speed sensor terminal A)
K	RF wheel-speed (-)	RF ABS wheel-speed sensor	Continuity	K-RF ABS wheel-speed sensor terminal B	Continuity detected	Wiring harness (K- RF ABS wheel-speed sensor terminal B)
L	RR wheel-speed (-)	RR ABS wheel-speed sensor	Continuity	L-RR ABS wheel-speed sensor terminal D	Continuity detected	Wiring harness (L- RR ABS wheel-speed sensor terminal D)
M	RR wheel-speed (+)	RR ABS wheel-speed sensor	Continuity	M-RR ABS wheel-speed sensor terminal B	Continuity detected	Wiring harness (M- RR ABS wheel-speed sensor terminal B)
N	-	-	-	-	-	-
O	Brake light	Brake light relay or brake light unit	Voltage	Brake pedal depressed	B+	Wiring harness (O- brake light relay or brake light unit)
O	Brake light	Brake light relay or brake light unit	Voltage	Brake pedal released	1 V or less	Wiring harness (O- brake light relay or brake light unit)
P	LR wheel-speed (-)	LR wheel-speed sensor	Continuity	P-LR ABS wheel-speed sensor terminal D	Continuity detected	Wiring harness (P- LR ABS wheel-speed sensor terminal D)
Q	-	-	-	-	-	-
R	LR wheel-speed (+)	LR ABS wheel-speed sensor	Continuity	R-LR ABS wheel-speed sensor terminal B	Continuity detected	Wiring harness (R- LR ABS wheel-speed sensor terminal B)
S	LF wheel-speed sensor (+)	LF ABS wheel-speed sensor	Continuity	S-LF ABS wheel-speed sensor terminal A	Continuity detected	Wiring harness S-LF ABS wheel-speed sensor terminal A)
T	-	-	-	-	-	-
U	-	-	-	-	-	-
V	-	-	-	-	-	-
W	LF wheel-speed sensor (-)	LF wheel-speed sensor	Continuity	W-LF ABS wheel-speed sensor terminal B	Continuity detected	Wiring harness (W- LF ABS wheel-speed sensor terminal B)
X	-	-	-	-	-	-
Y	-	-	-	-	-	-
Z	-	-	-	-	-	-
AA	-	-	-	-	-	-
AB	-	-	-	-	-	-
AC	-	-	-	-	-	-
AD	-	-	-	-	-	-
AE	-	-	-	-	-	-
AF	-	-	-	-	-	-
AG	-	-	-	-	-	-
AH	-	-	-	-	-	-
AI	-	-	-	-	-	-
AJ	-	-	-	-	-	-
AK	Ground	Ground point	Continuity	AK-ground point	Continuity detected	Wiring harness (AK- ground point)
AL	Ground	Ground point	Continuity	AL-ground point	Continuity detected	Wiring harness (AL- ground point)