Last Modified: 11-13-2015 6.6 D Doc ID: RM000004TIQ022X
Model Year Start: 2016 Model: Tacoma Prod Date Range: [08/2015 - ]
Title: CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING;
2016 MY Tacoma [08/2015 - ]
HOW TO PROCEED WITH TROUBLESHOOTING
1. PRECAUTIONS WHEN TROUBLESHOOTING
ecause the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting
using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.
If the CAN communication system is malfunctioning, check the contact pressure of the terminals in
connectors, as insufficient terminal contact pressure may be the cause .
Refer to Diagnosis System for CAN communication system DTCs.
Refer to troubleshooting of each system if DTCs regarding the CAN communication system are not output.
Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1
minute or more without operating the key, switches or opening or closing the doors. After that, disconnect
the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before
measuring the resistance.
After turning the ignition switch off, waiting time may be required before disconnecting the cable from the
negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative
(-) battery terminal notices before proceeding with work .
(a) CAN communication DTCs are output for CAN main bus and CAN branch malfunctions as well as for
internal malfunctions or power source malfunctions of ECUs or sensors for systems using CAN
communication. Therefore, when DTCs for internal malfunctions or power source malfunctions of
corresponding systems are output at the same time as CAN communication DTCs, troubleshoot according
to the internal malfunction and power source malfunction DTCs.
(b) The DLC3 branch and V bus main bus circuits can be checked for malfunctions by inspecting at the DLC3
terminals using an electrical tester.
hen inspecting at the DLC3 connector, do not connect the tester directly to the terminals. Instead,
connect using service wires.
Inspections for an open in an ECU or sensor branch, or inspections for buses other than the V bus cannot
be performed from the DLC3.
(c) An open in a branch for ECUs or sensors that are connected to the CAN main bus can be checked by
performing a CAN bus check using the Techstream. (This inspection is possible when the DLC3 branch and
V bus main bus lines are normal.)
(d) If the V bus had a communication error, the probable ECU or sensor for which communication stopped can
be determined using the combination of communication DTCs (DTCs that start with U) that are output.
(e) If a sub bus has a communication error, the gateway function equipped ECU (sub bus monitor ECU)
detects it and stores DTCs related to the error.
On the Techstream, gateway function equipped ECUs display DTCs for ECUs connected to the sub bus.
(f) When an open circuit is detected, before disconn
ecting related connectors for inspection, push in on the
connector body to check that the connector is not loose or disconnected.
(g) When a connector is disconnected, check that the terminals and connector body are not cracked, deformed