How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2007 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

DTCs for the CAN communication system are as follows: U0073, U0100, U0105, U0121, U0122, U0123, U0124, U0126, U0129, C1280, C1296, C1297, and B1499.
Refer to the troubleshooting procedures of each system if DTCs regarding the CAN communication system are not output.
Turn the ignition switch off before measuring the resistances of the main wire and the branch wire.
After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.
Before measuring the resistance, leave the vehicle for at least 1 minute and do not operate the ignition switch, any switches or doors. If doors need to be opened in order to check connectors, open the doors and leave them open.

HINT:

*: Use the intelligent tester (with CAN VIM).
Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

VEHICLE BROUGHT TO WORKSHOP
INSPECT BATTERY VOLTAGE
Standard voltage:

11 to 14 V

If the voltage is below 11 V, recharge or replace the battery before proceeding.
CHECK CAN BUS LINE
1. Check the CAN bus line (see CAN BUS LINE ).
CHECK INSTALLED SYSTEMS (ECU AND SENSOR) THAT USE CAN COMMUNICATION
CHECK AND CLEAR DTC*

CHECK INTELLIGENT TESTER VIA CAN VIM*

Select "COMMUNICATION BUS CHECK" (see DIAGNOSIS SYSTEM ).

Result

RESULT CHART

Result	Proceed to
All ECUs and sensors connected to CAN communication system displayed on screen.	A
One ECU or sensor connected to CAN communication system not displayed on screen.	B
2 or more ECU and sensors connected to CAN communication system not displayed on screen.	C

NOTE:

The systems (ECUs and sensors) that use CAN communication vary depending on the vehicle and option settings. Check which systems (ECUs and sensors) are installed on the vehicle (see DIAGNOSIS SYSTEM ).
Non-installed ECUs or sensors are not displayed. Do not mistake them for being in communication stop mode.
If 2 or more ECUs or sensors are not displayed on the intelligent tester, perform troubleshooting for open circuits in one side of the CAN branch line for each undisplayed ECU or sensor.

B: GO TO (appropriate COMMUNICATION STOP MODE):

Refer to PROBLEM SYMPTOMS TABLE

C: GO TO (appropriate OPEN IN ONE SIDE OF CAN BRANCH WIRE):

Refer to PROBLEM SYMPTOMS TABLE

A: Go TO NEXT STEP.

DTC COMBINATION TABLE
1. Confirm the trouble according to the combination of output DTCs regarding the CAN communication system.
  HINT:
  
  Previous CAN communication system DTCs may be the cause if CAN communication system DTCs are output and all ECUs and sensors connected to the CAN communication system are displayed on the intelligent tester "Communication BUS CHECK" screen.
2. Check the DTC combination table (see DIAGNOSIS SYSTEM ).
CIRCUIT INSPECTION
IDENTIFY PROBLEM
REPAIR OR REPLACE
CONFIRMATION TEST
END