Lost communication with the eCall unit (eCall unit)

1. Scan tool power-up check

1) Connect the scan tool.

2) Power up the scan tool. Does the scan tool power up?

Yes

=>Go to eCall unit communication verification.

No

Go to Scan tool does not power up.

Refer to "51.Engine Control 1A.Troubleshooting(RZ4E-TC) Scan tool does not power up".

2. eCall unit communication verification

1) Verify that communication can be established with the eCall unit. Can communication with the eCall unit be established?

Yes

Go to Intermittent conditions of body control system.

Refer to "223.Body Control 36D.Symptom(eCall unit) intermittent conditions of body control system".

No

=>Go to DLC inspection.

3. DLC inspection

1) Inspect for poor connections at the DLC (pins 6 and 14 of C19). Is the connection status normal?

Refer to "LHD Controller Area Network (Except Central Gateway C/U)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to Fuse inspection.

No

Repair the connections as necessary.

=>Go to Repair verification.

4. Fuse inspection

1) Inspect the following fuses for a blowout. Is the result normal?

  • ROOM(+B) 5A fuse
  • ELEC(IG2) 10A fuse

Yes

=>Go to eCall unit harness connector inspection.

No

Replace the fuse. If the fuse blows out again, repair the short to ground in the circuit relating to each fuse.

=>Go to Repair verification.

5. eCall unit harness connector inspection

1) Inspect for poor connections at the eCall unit harness connector (pins 8, 9, 10, 11, 16, 25, 26, and 32 of B85). Is the connection status normal?

Refer to "LHD eCall" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to Inspection for open circuit in eCall unit battery power supply circuit.

No

Repair the connections as necessary.

=>Go to Repair verification.

6. Inspection for open circuit in eCall unit battery power supply circuit

1) Turn OFF the ignition switch.

2) Disconnect the eCall unit harness connector (B85).

3) Connect a test lamp between the battery power supply circuit (pin 32 of B85) and the body ground. Does the test lamp illuminate?

Refer to "LHD eCall" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to Inspection for open circuit in eCall unit ignition power supply circuit.

No

Repair the open circuit or high resistance in the battery power supply circuit between ROOM(+B) 5A fuse and the eCall unit (pin 32 of B85).

=>Go to Repair verification.

7. Inspection for open circuit in eCall unit ignition power supply circuit

1) Connect a test lamp between the ignition power supply circuit (pin 16 of B85) and the body ground.

Refer to "LHD eCall" in the ETM (wiring diagram). (Open using the ETM viewer.).

2) Turn ON the ignition switch. Does the test lamp illuminate?

Yes

=>Go to eCall unit ground circuit inspection.

No

Repair the open circuit or high resistance in the ignition power supply circuit between the ELEC(IG2) 10A fuse and the eCall unit (pin 16 of B85).

=>Go to Repair verification.

8. eCall unit ground circuit inspection

1) Connect a test lamp between the battery power supply circuit (pin 32 of B85) and the ground circuit (pins 8, 11, 25, and 26 of B85). Does the test lamp illuminate?

Refer to "LHD eCall" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to CAN communication circuit inspection.

No

Repair the open circuit or high resistance in the ground circuit between the eCall unit (pins 8, 11, 25, and 26 of B85) and the body ground.

=>Go to Repair verification.

9. CAN communication circuit inspection

1) Inspect the CAN communication circuit between the eCall unit and the DLC for the following. Is the result normal?

Circuits to inspect

  • Between the eCall unit (pin 9 of B85) and the DLC (pin 6 of C19)
  • Between the eCall unit (pin 10 of B85) and the DLC (pin 14 of C19)

Inspection items

  • Open circuit or high resistance
  • Short together between circuits
  • Short to battery or short to ignition power supply circuit
  • Short to ground

Refer to "LHD Controller Area Network (Except Central Gateway C/U)" in the ETM (wiring diagram). (Open using the ETM viewer.).

2) Are all of the results normal?

Yes

=>Go to eCall unit replacement.

No

Repair the circuit as necessary.

=>Go to Repair verification.

10. eCall unit replacement

Note

  • Perform programming after replacing the eCall unit.

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control eCall unit removal".

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control eCall unit installation".

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control eCall unit setting".

Procedure completion

=>Go to Repair verification.

11. Repair verification

1) Securely connect the disconnected harness connectors.

2) Connect the scan tool.

3) Turn ON the ignition switch.

4) Verify that communication can be established with the eCall unit using the scan tool. Can communication with the eCall unit be established?

Yes

The system is normal.

No

=>Go to eCall unit harness connector inspection.