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 JUDGMENT 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-130 4WD-ECU connector and C-04 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-04 joint connector (CAN2) terminal No.5 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-04 joint connector (CAN2) terminal No.16 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

YES <vehicles without ASC> : Go to Step 3.
YES <vehicles with ASC> : Go to Step 2.
NO (the check result is not normal.) : Go to Step 7.

STEP 2. Check the wiring harness between C-209 steering wheel sensor connector and C-04 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-04 joint connector (CAN2) terminal No.4 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-04 joint connector (CAN2) terminal No.15 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

Go to Step 3.
Go to Step 8.

STEP 3. Check the wiring harness between C-301 ETACS-ECU connector and C-04 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-04 joint connector (CAN2) terminal No.6 <LHD> or 7 <RHD> and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-04 joint connector (CAN2) terminal No.19 <LHD> or 20 <RHD> and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

Go to Step 4.
Go to Step 9.

STEP 4. Check the wiring harness between B-06 engine-ECU connector <2000> or B-18 engine-ECU connector <2200> or B-30 engine-ECU connector <2400, 3000> and C-01 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-01 joint connector (CAN3) terminal No.4 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-01 joint connector (CAN3) terminal No.15 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

YES <A/T, CVT> : Go to Step 5.
YES <M/T> : Go to Step 6.
NO : Go to Step 10.

STEP 5. Check the wiring harness between C-136 CVT-ECU connector <CVT> or C-138 A/T-ECU connector <A/T> and C-01 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 .
  • Strictly observe the specified wiring harness repair procedure. 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-01 joint connector (CAN3) terminal No.7 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-01 joint connector (CAN3) terminal No.20 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

Go to Step 6.
Go to Step 11.

STEP 6. Check the wiring harness between A-02 ABS-ECU connector <vehicles without ASC> or A-03 ASC-ECU connector <vehicles with ASC> and C-01 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-01 joint connector (CAN3) terminal No.6 and body earth.
OK: 4.7 V or less
(4)Measure the voltage between C-01 joint connector (CAN3) terminal No.19 and body earth.
OK: 4.7 V or less

Q. Is the check result normal?

Check C-37 intermediate connector, and repair if necessary. If the intermediate connector is in good condition, repair the wiring harness between C-04 joint connector (CAN2) and C-01 joint connector (CAN3).
Go to Step 12.

STEP 7. M.U.T.-III CAN bus diagnostics (checking 4WD-ECU for internal short to power supply)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-130 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?

Check C-35 intermediate connector, and repair if necessary. If the intermediate connector is in good condition, repair the wiring harness between C-130 4WD-ECU connector and C-04 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 8. M.U.T.-III CAN bus diagnostics (checking the steering wheel sensor for internal short to power supply)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-209 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-209 steering wheel sensor connector and C-04 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 9. M.U.T.-III CAN bus diagnostics (checking the ETACS-ECU for internal short to power supply)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-301 ETACS-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-301 ETACS-ECU connector and C-04 joint connector (CAN2).

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

STEP 10. M.U.T.-III CAN bus diagnostics (checking the engine-ECU for internal short to power supply)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect B-06 engine-ECU connector <2000> or B-18 engine-ECU connector <2200> or B-30 engine-ECU connector <2400, 3000>, 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-06 engine-ECU connector <2000> or B-18 engine-ECU connector <2200> or B-30 engine-ECU connector <2400, 3000> and C-01 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 11. M.U.T.-III CAN bus diagnostics (checking the CVT-ECU <CVT> or A/T-ECU <A/T> for internal short to power supply)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect C-136 CVT-ECU connector or C-138 A/T-ECU connector <A/T>, 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-136 CVT-ECU connector <CVT> or C-138 A/T-ECU connector <A/T> and C-01 joint connector (CAN3).

Check the CVT-ECU connector <CVT> or A/T-ECU connector <A/T>, and repair if necessary. If the CVT-ECU connector <CVT> or A/T-ECU connector <A/T> is in good condition, replace the CVT-ECU <CVT> or A/T-ECU <A/T>.

STEP 12. M.U.T.-III CAN bus diagnostics (checking the ABS-ECU <vehicles without ASC> or ASC-ECU <vehicles with ASC> for internal short to power supply)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect A-02 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-02 ABS-ECU connector <vehicles without ASC> or A-03 ASC-ECU connector <vehicles with ASC> and C-01 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>.