Checking the voltage at the terminals of the ABS control unit (Honda Civic 7)

1. Using a voltmeter, check the voltage at the terminals of the ABS control unit connector.

2. Compare the measured values with those given in the table "Voltage at the terminals of the ABS control unit". If necessary, repair or replace the faulty element.

Table. ABS system fault codes.

Fault code	Malfunction	Possible location of the malfunction
11	Open or short circuit in the front right wheel speed sensor circuit	Wheel Speed Sensor Wheel Speed Sensor Rotor Wiring
12	Incorrect signal (signal distortion or sudden change in signal) front right wheel speed sensor
13	Open or short circuit in the front left wheel speed sensor circuit
14	Incorrect signal (signal distortion or sudden change in signal) front left wheel speed sensor
15	Open or short circuit in the rear right wheel speed sensor circuit
16	Incorrect signal (signal distortion or sudden change in signal) rear right wheel speed sensor
17	Open or short circuit in the rear left wheel speed sensor circuit
18	Incorrect signal (signal distortion or sudden change in signal) rear left wheel speed sensor
21	Front right wheel speed sensor rotor malfunction
22	Front left wheel speed sensor rotor malfunction	Wheel speed sensor rotor
23	Rear right wheel speed sensor rotor malfunction
24	Rear left wheel speed sensor rotor malfunction
31	Malfunction of the electromagnetic valve of the pressure modulator	Solenoid Valve ABS Control Unit Wiring
32
33
34
35
36
37
38
41	Front right locks up when ABS system is operating	Wheel Speed Sensor Wheel Speed Sensor Rotor ABS Control Unit Pressure Modulator Wiring
42	Front left locks up when ABS system is operating
43	Rear right locks when ABS system is operating
44	Rear left locks up when ABS system is operating
51	ABS pump motor lockout	Fuse #10 in the fuse box (in the engine compartment) Pressure Modulator ABS Control Unit Wiring
52	ABS pump motor does not turn on	ABS pump motor ABS control unit Fuse #10 in the fuse box (in the engine compartment) Wiring
53	ABS pump motor does not turn off (works constantly)	ABS pump motor ABS control unit
54	ABS Fail Safe Relay Malfunction	Pressure Modulator ABS Control Unit Wiring
61	Low voltage on emergency mode relay	Power Supply Wiring
62	High voltage on emergency mode relay
71	The wheels installed on the car have different sizes	Wheels of different sizes are installed. Tire pressure is not the same
81	ABS control unit malfunction	ABS control unit

Table. Voltage at the terminals of the ABS control unit.

Conclusion	Signal	Conclusions for verification	Verification conditions	Voltage, V
2	FRW (-)	2-18	The front right wheel rotates at 1 rpm	0.053 V or more (AC)
3	FLW (+)	3-12	The front left wheel rotates at 1 rpm	0.053 V or more (AC)
4	STOP	4-GND	The brake pedal is pressed	VB
			The brake pedal is not pressed	Less than 0.3 V
5	RLW (+)	5-14	The rear left wheel rotates at 1 rpm	0.053 V or more (AC)
6	RRW (-)	6-15	The rear right wheel rotates at 1 rpm	0.053 V or more (AC)
7	WALP	7-GND	Ignition is on	≈6 V
8	FSR+B	8 - GND	Constantly	VB
9	MR+B	9-GND	Constantly	VB
10	DLC	-	-	-
11	EBD	11 - GND	Parking brake on	Less than 0.3 V
			The parking brake is released	VB
12	FLW (-)	12-3	The front left wheel rotates at 1 rpm	0.053 V or more (AC)
13	SCS	-	-	-
14	RLW (-)	14-5	The rear left wheel rotates at 1 rpm	0.053 V or more (AC)
15	RRW (+)	15-6	The rear right wheel rotates at 1 rpm	0.053 V or more (AC)
16	IG2	16-GND	Ignition is on	VB
18	FRW (-)	18-2	The front right wheel rotates at 1 rpm	0.053 V or more (AC)
24	GND1	-	-	-
25	GND2	-	-	-

Note:

• AC - measurements are taken in alternating current mode;
• V_B - battery voltage.

[Based on materials from the website: HondaBook.ru]