4E-19 ABS:
Trouble shooting
Step
1
Scan tool communication check
Can scan tool communicate with BCM?
2
ABS hydraulic unit / control module assembly power
and ground circuit check
1) Check that ABS hydraulic unit / control module assembly
power supply circuit and ground circuit is in good
condition referring to "ABS Hydraulic Unit / Control
Module Assembly Power and Ground Circuit Check".
Are check results OK?
3
Data link connector power source circuit check
1) Disconnect scan tool from data link connector.
2) Check for proper connection to scan tool.
3) If OK then turn ignition switch to ON position, and
measure voltage between terminal B of data link
connector and vehicle body ground.
Is voltage 10 – 12 V?
4
Data link connector ground circuit check
1) Turn ignition switch to OFF position, and measure
resistance between the following terminals:
• Terminal G of data link connector and vehicle body
ground.
• Terminal G1 of data link connector and vehicle body
ground.
Are resistance less than 2
5
Serial communication circuit check
1) Turn ignition switch to OFF position.
2) Disconnect connectors of all control modules
communicating by serial data circuit.
3) Check proper connection at serial data circuit terminals.
4) If OK, then check for high resistance, open or short to
power circuit or ground in serial data circuit.
Is check result in good condition?
6
CAN communication line circuit check
1) Disconnect connectors of all control modules
communicating by means of CAN.
2) Check for proper connection to CAN communication line
wire.
3) If OK then check CAN communication line circuit
between control modules for open, short and high
resistance.
Is each CAN communication line circuit in good condition?
Action
Ω
?
Yes
Go to Step 2.
Go to Step 3.
Go to Step 4.
Go to Step 5.
Go to Step 6.
Substitute a known-
good ABS hydraulic unit
/ control module
assembly and recheck.
No
Go to Step 3.
Repair ABS hydraulic
unit / control module
assembly power or
ground circuit.
Terminal B circuit open
or shorted to ground.
Terminal G and/or G1
wire circuit open or high
resistance.
Repair serial data circuit
and recheck.
Repair CAN
communication line
circuit and recheck.