| Symptom | Trouble Area |
|---|---|
| Check CAN Communication Connection | ·
CAN branch line or connector ·
Power source circuit of central gateway ECU (network gateway ECU) ·
Central gateway ECU (network gateway ECU) ground circuit ·
Central gateway ECU (network gateway ECU) ·
Power source circuit of DLC3 ·
DLC3 ground circuit |
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
Because 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.
Inspect the fuses for circuits related to this system before performing the following procedure.
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 or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 10 minutes or more before measuring the resistance.
After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) battery terminal.
When disconnecting and reconnecting the battery.
When disconnecting and reconnecting the battery, there is an automatic learning function that completes learning when the respective system is used.
Some parts must be initialized and set when replacing or removing and installing parts.
After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.
DTC check procedure: Turn the ignition switch to ON and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.
After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.
Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.
When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.
Read the GTS operator's manual before use.
Connect the GTS to the DLC3 of another vehicle.
Turn the ignition switch to ON.
Turn the GTS on.
Check that the GTS and ECUs can communicate with the ignition switch ON.
ECUs and sensors are not displayed on the "Communication Bus Check" screen when the GTS cannot communicate with the vehicle.
If communication between the GTS and ECUs is not possible, either the GTS or vehicle has a malfunction.
If communication between the GTS and ECUs is still not possible even when the GTS is connected to another vehicle, the GTS has a malfunction. Perform the self tests described in the GTS operator's manual. (The GTS may be malfunctioning or its battery may be discharged.)
| Result | Proceed to |
|---|---|
| OK (Communication between the GTS and the vehicle is not possible, but communication is possible when connected to another vehicle.) | A |
| NG (Communication is not possible between the GTS and the vehicle, or between the GTS and another vehicle.) | B |
A
B
Confirm error on the GTS screen.
| Result | Proceed to |
|---|---|
| "A communication error with Engine ECU occurred. Please confirm that Engine ECU is properly installed." is displayed. | A |
| Cannot proceed to vehicle selection screen. | B |
A
B
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 or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 10 minutes or more before measuring the resistance.
Operating the ignition switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
Disconnect the cable from the negative (-) battery terminal.
| *a | Component with harness connected
(Central Gateway ECU (Network Gateway ECU)) |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition | Result |
|---|---|---|---|
| G174-26 (CA4H) - G174-25 (CA4L) | Cable disconnected from negative (-) battery terminal | 54 to 69 Ω | Below 54 Ω: Short circuit between bus lines |
| 70 Ω or higher: Open circuit in main bus lines | |||
| G174-26 (CA4H) - Body ground | Cable disconnected from negative (-) battery terminal | 200 Ω or higher | Below 200 Ω: CANH short to ground |
| G174-25 (CA4L) - Body ground | Cable disconnected from negative (-) battery terminal | 200 Ω or higher | Below 200 Ω: CANL short to ground |
| G174-26 (CA4H) - Positive (+) battery terminal | Cable disconnected from negative (-) battery terminal | 6 kΩ or higher | Below 6 kΩ: CANH +B short |
| G174-25 (CA4L) - Positive (+) battery terminal | Cable disconnected from negative (-) battery terminal | 6 kΩ or higher | Below 6 kΩ: CANL +B short |
| Result | Proceed to |
|---|---|
| OK (CAN bus main lines are normal) | A |
| NG (There is an open or short in a CAN bus main line of a suspected bus) | B |
A
Inspect the ECM supply power or VC voltage.
B
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 or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 10 minutes or more before measuring the resistance.
Operating the ignition switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
| *a | Front view of DLC3 |
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G114-16 (BAT) - Body ground | Always | 11 to 14 V |
If the resistance between CANH and CANL is not as specified, a connector may have been loose or disconnected during inspection. If a connector is loose or disconnected, connect it and perform the inspection again.
Disconnect the cable from the negative (-) battery terminal.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G114-4 (CG) - Body ground | Cable disconnected from negative (-) battery terminal | Below 1 Ω |
If the resistance between CANH and CANL is not as specified, a connector may have been loose or disconnected during inspection. If a connector is loose or disconnected, connect it and perform the inspection again.
| Proceed to |
|---|
| OK |
| NG |
OK
NG
| *a | Front view of DLC3 |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G114-6 (CANH) - G114-14 (CANL) | Cable disconnected from negative (-) battery terminal | Below 70 Ω |
If the resistance between CANH and CANL is not as specified, a connector may have been loose or disconnected during inspection. If a connector is loose or disconnected, connect it and perform the inspection again.
| Proceed to |
|---|
| OK |
| NG |
OK
NG
| *a | Front view of DLC3 |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G114-6 (CANH) - G114-14 (CANL) | Cable disconnected from negative (-) battery terminal | 54 Ω or higher |
| G114-6 (CANH) - G114-4 (CG) | Cable disconnected from negative (-) battery terminal | 200 Ω or higher |
| G114-14 (CANL) - G114-4 (CG) | ||
| G114-6 (CANH) - G114-16 (BAT) | Cable disconnected from negative (-) battery terminal | 6 kΩ or higher |
| G114-14 (CANL) - G114-16 (BAT) |
If the resistance between CANH and CANL is not as specified, a connector may have been loose or disconnected during inspection. If a connector is loose or disconnected, connect it and perform the inspection again.
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Disconnect the central gateway ECU (network gateway ECU) connector.
Measure the resistance according to the value(s) in the table below.
| *a | Front view of wire harness connector
(to Central Gateway ECU (Network Gateway ECU)) |
- | - |
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G174-22 (GND) - Body ground | Cable disconnected from negative (-) battery terminal | Below 1 Ω |
Reconnect the cable to the negative (-) battery terminal.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G174-1 (BATT) - Body ground | Always | 11 to 14 V |
| G174-2 (ACC) - Body ground | Ignition switch ACC | 11 to 14 V |
| Ignition switch off | Below 1 V | |
| G174-19 (IGP) - Body ground | Ignition switch ON | 11 to 14 V |
| Ignition switch off | Below 1 V | |
| G174-20 (IGR) - Body ground | Ignition switch ON | 11 to 14 V |
| Ignition switch off | Below 1 V |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Disconnect the G174 central gateway ECU (network gateway ECU) connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G174-16 (CA6H) - G114-6 (CANH) | Cable disconnected from negative (-) battery terminal | Below 1 Ω |
| G174-17 (CA6L) - G114-14 (CANL) |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Disconnect the central gateway ECU (network gateway ECU) connector.
Measure the resistance according to the value(s) in the table below.
| *a | Front view of wire harness connector
(to Central Gateway ECU (Network Gateway ECU)) |
*b | Front view of DLC3 |
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G174-16 (CA6H) - G174-17 (CA6L) | Cable disconnected from negative (-) battery terminal | 54 to 69 Ω |
| G174-16 (CA6H) - G114-4 (CG) | Cable disconnected from negative (-) battery terminal | 200 Ω or higher |
| G174-17 (CA6L) - G114-4 (CG) | ||
| G174-16 (CA6H) - G114-16 (BAT) | Cable disconnected from negative (-) battery terminal | 6 kΩ or higher |
| G174-17 (CA6L) - G114-16 (BAT) |
| Proceed to |
|---|
| OK |
| NG |
OK
NG