9.6.6. ABS diagnostics

In case of malfunction of system possibly carrying out diagnostics. Compound ABS units are not subject to adjustment and in case of failure are replaced.

Fig. 7.23. Numbering of conclusions of the EBU ABS socket

Check of electric chains of ABS is made on a shtekerny block of the EBU socket (fig. 7.23).

It is forbidden to connect extension pieces of verifying devices (an ohmmeter or the voltmeter) to EBU socket tips. For this purpose it is necessary to remove a plastic protective cap from a socket block from a supply of electricity cables or to use the transitional I will corrode. Watch that numbering of conclusions on a block of wires of the EBU socket coincided with numbering of conclusions of a block of the transitional socket.

Before replacing the hydrounit, EBU or other expensive units, it is recommended to make more careful check of ABS by means of the Nissan firm CONSULT device.

For carrying out check at the switched-off ignition disconnect a shtekerny block of EBU. All other shtekerny sockets of ABS system should be connected. The stoplight switch also should not be disconnected. Check make according to tab. 7.2 and 7.3.

check No.	Device connection	Conditions of carrying out check	Expected result of measurement	Possible place of malfunction
1	Conclusion «4» sockets of the relay and "weight"	Ignition is switched off	U=Uакк. Bath.	Fuse D (30 And) or electroconducting
2	Conclusion «4» sockets of the relay and "weight"		The same	Fuse C (30 And) or electroconducting
3	Conclusion of "1" socket of the switch of a stoplight and "weight"		»	Fuse No. 14 (10 And) or electroconducting
4	Conclusion of "1" EBU and "weight"	Ignition is included	»	Fuse No. 12 (7,5 And) or electroconducting
5	Conclusion of "30" EBU and "weight"		»	Fuse No. 8 (10 And) or electroconducting
6	Conclusion «7» sockets of diagnostics and "weight"		»	Fuse No. 7 (7,5 And) or electroconducting
7	Conclusion «19» sockets of the hydrounit and "weight"		»	Relay of a food of electromagnetic valves
8	Conclusion of "48" EBU and "weight"	Ignition is switched off, the pedal of a brake is released	U=0	Stoplight switch
9	Conclusions «28», «29» or «39» EBU and "weight"	Ignition is switched off. EBU is connected on "weight" (the storage battery is disconnected)	RЈ0,5 Oм	Electroconducting or point of connection of "weight"

check No.	EBU socket conclusion	The checked sensor	Conditions of carrying out check	Expected result of measurement	Possible place of malfunction
2/1	«15» and «14»	Forward right wheel	The switch of ignition or devices and starter is switched off	0,8-1,2 kiloohms	Sensor, connections of wires or wire
2/2	«9» and «10»	Forward left wheel
2/3	«11» and «38»	Back right wheel
2/4	«13» and «12»	Back left wheel

Before carrying out diagnostics be convinced of tightness of the vacuum amplifier, in absence of squeezing of hoses of brake system and their tightness. Add brake liquid in a system tank to normal level. At operations with shtekerny blocks pay attention to a condition of their conclusions, spring locks and existence of rubber laying.

The scheme of electric chains of ABS system is provided in a color tab at the end of the book.