Diagnosis Item 5: Diagnose shorts in the power supply to CAN-C bus line



caution When servicing a CAN bus line, earth yourself by touching a metal object such as an unpainted water pipe. If you fail to do, a component connected to the CAN bus line may be broken.

FUNCTION




TROUBLE JUDGEMENT CONDITIONS




TROUBLESHOOTING HINTS



  • Malfunction of the connector (short to power supply in connector)
  • Malfunction of the wiring harness (short to power supply in the CAN-C main or sub bus lines)
  • Malfunction of the ECU (ETACS-ECU, or ECUs on CAN-C lines failed)

DIAGNOSIS PROCEDURE


STEP 1. Check the wiring harness between C-411 ETACS-ECU connector and C-202 joint connector (CAN2) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN2), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-202 joint connector (CAN2) terminal No.11 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-202 joint connector (CAN2) terminal No.22 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

YES <4WD> : Go to Step 2.
YES <2WD (Vehicles with ASC or headlamp automatic levelling system> : Go to Step 3.
YES <2WD (Vehicles with reversing sensor system and Vehicles without ASC and headlamp automatic levelling system> : Go to Step 4.
YES <Vehicles without ASC, headlamp automatic levelling system and reversing sensor system> : Go to Step 5.
NO : Go to Step 11.

STEP 2. Check the wiring harness between C-228 4WD-ECU connector and C-202 joint connector (CAN2) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN2), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-202 joint connector (CAN2) terminal No.8 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-202 joint connector (CAN2) terminal No.19 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

Go to Step 3.
Go to Step 12.

STEP 3. Check the wiring harness between C-310 steering wheel sensor connector and C-202 joint connector (CAN2) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN2), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-202 joint connector (CAN2) terminal No.9 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-202 joint connector (CAN2) terminal No.20 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

YES <Vehicles with reversing sensor system> : Go to Step 4.
YES <Vehicles without reversing sensor system> : Go to Step 5.
NO : Go to Step 13.

STEP 4. Check the wiring harness between C-13 corner sensor/back sensor-ECU connector and C-202 joint connector (CAN2) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN2), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-202 joint connector (CAN2) terminal No.7 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-202 joint connector (CAN2) terminal No.18 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

Go to Step 5.
Go to Step 14.

STEP 5. Check the wiring harness between B-10 <diesel> or B-27 <petrol> engine-ECU connector and C-24 joint connector (CAN3) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN3), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-24 joint connector (CAN3) terminal No.7 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-24 joint connector (CAN3) terminal No.18 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

YES <CVT> : Go to Step 6.
YES <M/T (Vehicles with automatic stop & go system)> : Go to Step 7.
YES <M/T (Vehicles without automatic stop & go system)> : Go to Step 8.
NO : Go to Step 15.

STEP 6. Check the wiring harness between C-131 CVT-ECU connector and C-24 joint connector (CAN3) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN3), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-24 joint connector (CAN3) terminal No.5 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-24 joint connector (CAN3) terminal No.16 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

Go to Step 7.
Go to Step 16.

STEP 7. Check the wiring harness between C-11 AS&G-ECU connector and C-24 joint connector (CAN3) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN3), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-24 joint connector (CAN3) terminal No.6 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-24 joint connector (CAN3) terminal No.17 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

Go to Step 8.
Go to Step 17.

STEP 8. Check the wiring harness between C-221 EPS-ECU connector and C-24 joint connector (CAN3) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN3), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-24 joint connector (CAN3) terminal No.9 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-24 joint connector (CAN3) terminal No.20 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

YES <Vehicles with headlamp automatic levelling system> : Go to Step 9.
YES <Vehicles without headlamp automatic levelling system> : Go to Step 10.
NO : Go to Step 18.

STEP 9. Check the wiring harness between C-117 headlamp automatic levelling-ECU connector and C-24 joint connector (CAN3) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN3), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-24 joint connector (CAN3) terminal No.10 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-24 joint connector (CAN3) terminal No.21 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

Go to Step 10.
Go to Step 19.

STEP 10. Check the wiring harness between A-67 ABS-ECU <Vehicles without ASC> or A-03 ASC-ECU <Vehicles with ASC> connector and C-24 joint connector (CAN3) for short to power supply (voltage measurement).


caution
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
(1)Disconnect joint connector (CAN3), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-24 joint connector (CAN3) terminal No.8 and body earth
OK: 4.7 V or less
(4)Measure the voltage between C-24 joint connector (CAN3) terminal No.19 and body earth
OK: 4.7 V or less

Q. Is the check result normal?

Check C-128 intermediate connector, and repair if necessary. If the intermediate connector is in good condition, repair the wiring harness between C-202 joint connector (CAN2) and C-24 joint connector (CAN3).
Go to Step 20.

STEP 11. Check the wiring harness between C-411 ETACS-ECU connector and C-202 joint connector (CAN2) for short to power supply (voltage measurement).


caution
  • Disconnect the negative battery terminal. For details refer to .
  • A digital multimeter should be used. For details refer to .
  • The test wiring harness should be used. For details refer to .
  • Strictly observe the specified wiring harness repair procedure. For details refer to .
(1)Disconnect ETACS-ECU connector and joint connector (CAN2), and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between C-202 joint connector (CAN2) terminal No.11 and body earth. <CAN_H>
OK: 1 V or less
(4)Measure the voltage between C-202 joint connector (CAN2) terminal No.22 and body earth. <CAN_L>
OK: 1 V or less

Q. Is the check result normal?

Check the ETACS-ECU connector, replace and repair if necessary. If the ETACS-ECU connector is in good condition, ETACS-ECU.
Repair the wiring harness between C-411 ETACS-ECU connector and C-202 joint connector (CAN2).

STEP 12. M.U.T.-III CAN bus diagnostics (checking the 4WD-ECU for internal short to earth)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-228 4WD-ECU connector, and diagnose the CAN bus line.

OK: The display of the M.U.T.-III is as shown in the figure.

Q. Does M.U.T.-III screen correspond to the illustration?

Repair the wiring harness between C-228 4WD-ECU connector and C-202 joint connector (CAN2).

Check the 4WD-ECU connector, and repair if necessary. If the 4WD-ECU connector is in good condition, replace the 4WD-ECU.

STEP 13. M.U.T.-III CAN bus diagnostics (checking the steering wheel sensor for internal short to earth)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-310 steering wheel sensor connector, and diagnose the CAN bus line.

OK: The display of the M.U.T.-III is as shown in the figure.

Q. Does M.U.T.-III screen correspond to the illustration?

Repair the wiring harness between C-310 steering wheel sensor connector and C-202 joint connector (CAN2).

Check the steering wheel sensor connector, and repair if necessary. If the steering wheel sensor connector is in good condition, replace the steering wheel sensor.

STEP 14. M.U.T.-III CAN bus diagnostics (checking the corner sensor/back sensor-ECU for internal short to earth)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-13 corner sensor/back sensor-ECU connector, and diagnose the CAN bus line.

OK: The display of the M.U.T.-III is as shown in the figure.

Q. Does M.U.T.-III screen correspond to the illustration?

Repair the wiring harness between C-13 corner sensor/back sensor-ECU connector and C-202 joint connector (CAN2).

Check the corner sensor/back sensor-ECU connector, and repair if necessary. If the corner sensor/back sensor-ECU connector is in good condition, replace the corner sensor/back sensor-ECU.

STEP 15. M.U.T.-III CAN bus diagnostics (checking the headlamp automatic levelling-ECU for internal short to earth)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect B-10 <diesel> or B-27 <petrol> engine-ECU connector, and diagnose the CAN bus line.

OK: The display of the M.U.T.-III is as shown in the figure.

Q. Does M.U.T.-III screen correspond to the illustration?

Repair the wiring harness between B-10 <diesel> or B-27 <petrol> engine-ECU and C-24 joint connector (CAN3).

Check the engine-ECU connector, and repair if necessary. If the engine-ECU connector is in good condition, replace the engine-ECU.

STEP 16. M.U.T.-III CAN bus diagnostics (checking the CVT-ECU for internal short to earth)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-131 CVT-ECU connector, and diagnose the CAN bus line.

OK: The display of the M.U.T.-III is as shown in the figure.

Q. Does M.U.T.-III screen correspond to the illustration?

Repair the wiring harness between C-131 CVT-ECU connector and C-24 joint connector (CAN3).

Check the CVT-ECU connector, and repair if necessary. If the CVT-ECU connector is in good condition, replace the CVT-ECU connector.

STEP 17. M.U.T.-III CAN bus diagnostics (checking the AS&G-ECU for internal short to earth)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-11 AS&G-ECU connector, and diagnose the CAN bus line.

OK: The display of the M.U.T.-III is as shown in the figure.

Q. Does M.U.T.-III screen correspond to the illustration?

Repair the wiring harness between C-11 AS&G-ECU connector and C-24 joint connector (CAN3).

Check the AS&G-ECU connector, and repair if necessary. If the AS&G-ECU connector is in good condition, replace the AS&G-ECU.

STEP 18. M.U.T.-III CAN bus diagnostics (checking the EPS-ECU for internal short to earth)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-221 EPS-ECU connector, and diagnose the CAN bus line.

OK: The display of the M.U.T.-III is as shown in the figure.

Q. Does M.U.T.-III screen correspond to the illustration?

Repair the wiring harness between C-221 EPS-ECU connector and C-24 joint connector (CAN3).

Check the EPS-ECU connector, and repair if necessary. If the EPS-ECU connector is in good condition, replace the EPS-ECU.

STEP 19. M.U.T.-III CAN bus diagnostics (checking the headlamp automatic levelling-ECU for internal short to earth)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-117 headlamp automatic levelling-ECU connector, and diagnose the CAN bus line.

OK: The display of the M.U.T.-III is as shown in the figure.

Q. Does M.U.T.-III screen correspond to the illustration?

Repair the wiring harness between C-117 headlamp automatic levelling-ECU connector and C-24 joint connector (CAN3).

Check the headlamp automatic levelling-ECU connector, and repair if necessary. If the headlamp automatic levelling-ECU connector is in good condition, replace the headlamp automatic levelling-ECU.

STEP 20. M.U.T.-III CAN bus diagnostics (checking the ABS-ECU <vehicles without ASC> or ASC-ECU <vehicles with ASC> for internal short to earth)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect A-67 ABS-ECU connector <vehicles without ASC> or A-03 ASC-ECU connector <vehicles with ASC>, and diagnose the CAN bus line.

OK: The display of the M.U.T.-III is as shown in the figure.

Q. Does M.U.T.-III screen correspond to the illustration?

Repair the wiring harness between A-67 ABS-ECU connector <vehicles without ASC> or A-03 ASC-ECU connector <vehicles with ASC> and C-24 joint connector (CAN3).

Check the ABS-ECU connector <vehicles without ASC> or ASC-ECU connector <vehicles with ASC>, and repair if necessary. If the ABS-ECU connector <vehicles without ASC> or ASC-ECU connector <vehicles with ASC> is in good condition, replace the ABS-ECU <vehicles without ASC> or ASC-ECU <vehicles with ASC>.