1) Connect the scan tool.
2) Power up the scan tool. Does the scan tool power up?
Yes
=>Go to Scan tool communication verification.
No
Go to Scan tool does not power up.
Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) Scan tool does not power up".
Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 without DPD) Scan tool does not power up".
Refer to "51.Engine Control 1A.Troubleshooting(RZ4E-TC) Scan tool does not power up".
1) Check the communication status with the BCM using the scan tool. Is communication with the BCM established?
Yes
Go to Intermittent conditions of body control system.
Refer to "223.Body Control 36D.Symptom(BCM) intermittent conditions of body control system".
No
=>Go to Central gateway control unit communication verification.
1) Verify communication with the central gateway control unit using the scan tool. Can communication with the central gateway control unit be established?
Yes
=>Go to Body CAN communication circuit communication verification.
No
Go to Lost communication with the central gateway control unit.
1) Verify that communication can be established with the following control modules using a scan tool. Can communication with all the control modules be established?
Yes
=>Go to BCM harness connector inspection.
No
Go to Body CAN communication circuit inspection.
Refer to "64.Body Control 10I.Troubleshooting(Central GateWay) body CAN communication circuit inspection".
1) Inspect for poor connections at the BCM harness connector (pins 3 and 4 of B18). Is the connection status normal?
Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Yes
No
Repair the connections as necessary.
1) Inspect the following fuses. Is the result normal?
Yes
=>Go to Inspection for open circuit in BCM battery power supply circuit 1.
No
Replace the fuse. If the fuse blows out again, repair the short to ground in the circuits relating to each fuse.
1) Turn OFF the ignition switch.
2) Disconnect the BCM harness connector (B17).
3) Connect a test lamp between the battery power supply circuit (pin 2 of B17) and the body ground. Does the test lamp illuminate?
Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Yes
=>Go to Inspection for open circuit in BCM battery power supply circuit 2.
No
Repair the open circuit or high resistance in battery power supply circuit 1 between the BCM BATT1 25A fuse and the BCM (pin 2 of B17).
1) Connect a test lamp between the battery power supply circuit (pin 1 of B17) and the body ground. Does the test lamp illuminate?
Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Yes
=>Go to Inspection for open circuit in BCM battery power supply circuit 3.
No
Repair the open circuit or high resistance in battery power supply circuit 2 between the BCM BATT2 25A fuse and the BCM (pin 1 of B17).
1) Connect a test lamp between the battery power supply circuit (pin 3 of B17) and the body ground. Does the test lamp illuminate?
Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Yes
=>Go to Inspection for open circuit in BCM ignition power supply circuit.
No
Repair the open circuit or high resistance in battery power supply circuit 3 between the BCM BATT3 20A fuse and the BCM (pin 3 of B17).
1) Connect a test lamp between the ignition power supply circuit (pin 13 of B19) and the body ground.
Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).
2) Turn ON the ignition switch. Does the test lamp illuminate?
Yes
=>Go to BCM ground circuit inspection.
No
Repair the open circuit or high resistance in the ignition power supply circuit between the ELEC IG1 10A fuse and the BCM (pin 13 of B19).
1) Inspect the ground circuit between the BCM (pin 23 of B16, pins 9 and 10 of B20) and the body ground for the following. Is the result normal?
Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Yes
=>Go to Body CAN communication circuit inspection.
No
Repair the circuit as necessary.
1) Inspect the CAN High circuit and the CAN Low circuit between the BCM (pins 4 and 3 of B18) and the central gateway control unit (pins 3 and 4 of B41) for the following. Is the result normal?
Refer to "LHD Controller Area Network (Central Gateway C/U)" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Controller Area Network (Central Gateway C/U (4JJ3 with DPD))" in the ETM (wiring diagram). (Open using the ETM viewer.).
Refer to "RHD Controller Area Network (Central Gateway C/U (4JJ3 without DPD, RZ4E))" in the ETM (wiring diagram). (Open using the ETM viewer.).
2) Are all of the results normal?
Yes
No
Repair the circuit or connection as necessary.
Note
Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control BCM removal".
Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control BCM installation".
Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control BCM setting".
Procedure completion
1) Turn OFF the ignition switch.
2) Reconnect all of the disconnected harness connectors.
3) Turn ON the ignition switch.
4) Check the communication status with the BCM using the scan tool. Is communication with the BCM established?
Yes
The system is normal.
No
=>Go to Central gateway control unit communication verification.