Diagnosis Item 10: Diagnose when the M.U.T.-III cannot receive the data sent by engine-ECU


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 [joint connector (CAN3) or engine-ECU connector improperly connected]
  • Malfunction of the wiring harness [open circuit between the engine-ECU and the joint connector (CAN3), power supply circuit to the engine-ECU]
  • Malfunction of the engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: 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)
caution The strand end of the twist wire should be within 10 cm from the connector. For details refer to .

Q. Is the check result normal?
Go to Step 2.
Repair the defective connector.

STEP 2. 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)
caution Strictly observe the specified wiring harness repair procedure. For details refer to .
(1)Disconnect engine-ECU connector and joint connector (CAN3), and check the following wiring harness.
(2)Check that there is continuity between B-06 engine-ECU connector terminal No.83 and C-01 joint connector (CAN3) terminal No.4 <2000 - CAN_H>
OK: Continuity exists (2 Ω or less)
(3)Check that there is continuity between B-06 engine-ECU connector terminal No.104 and C-01 joint connector (CAN3) terminal No.15 <2000 - CAN_L>
OK: Continuity exists (2 Ω or less)
(4)Check that there is continuity between B-18 engine-ECU connector terminal No.13 and C-01 joint connector (CAN3) terminal No.4 <2200 - CAN_H>
OK: Continuity exists (2 Ω or less)
(5)Check that there is continuity between B-18 engine-ECU connector terminal No.1 and C-01 joint connector (CAN3) terminal No.15 <2200 - CAN_L>
OK: Continuity exists (2 Ω or less)
(6)Check that there is continuity between B-30 engine-ECU connector terminal No.90 and C-01 joint connector (CAN3) terminal No.4 <2400 - CAN_H, 3000 - CAN_H>
OK: Continuity exists (2 Ω or less)
(7)Check that there is continuity between B-30 engine-ECU connector terminal No.91 and C-01 joint connector (CAN3) terminal No.15 <2400 - CAN_L, 3000 - CAN_L>
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Check the power supply circuit of the engine-ECU. Refer to GROUP 13A - Troubleshooting <2000>, GROUP 13C - Troubleshooting <3000>, GROUP 13D - Troubleshooting <2400> or GROUP 13E - Troubleshooting <2200>.
Repair the wiring harness.