Diagnosis Procedure

WARNING: This page is about a different car, the 2016 Infiniti Q50. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION:

Since hybrid vehicles and electric vehicles contain a high voltage battery, there is the risk of electric shock, electric leakage, or similar accidents if the high voltage component and vehicle are handled incorrectly. Be sure to follow the correct work procedures when performing inspection and maintenance.

WARNING:

Be sure to remove the service plug in order to disconnect the high voltage circuits before performing inspection or maintenance of high voltage system harnesses and parts.
The removed service plug must always be carried in a pocket of the responsible worker or placed in the tool box during the procedure to prevent the plug from being connected by mistake.
Be sure to wear insulating protective equipment before beginning work on the high voltage system.
Never allow workers other than the responsible person to touch the vehicle containing high voltage parts. To keep others from touching the high voltage parts, these parts must be covered with an insulating sheet except when using them.
Refer to HIGH VOLTAGE PRECAUTIONS .

CAUTION:

Never bring the vehicle into the READY status with the service plug removed unless otherwise instructed in the Service Information. A malfunction may occur if this is not observed.

PRECONDITIONING

WARNING:
Follow the instructions below before starting the procedure.
1. Disconnect high voltage circuit. Refer to HOW TO DISCONNECT HIGH VOLTAGE .
2. Check voltage in high voltage circuit. Refer to CHECK VOLTAGE IN HIGH VOLTAGE CIRCUIT .
GO TO STEP 2 .

CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the 12V battery cable from the negative terminal.
3. Disconnect all the control unit connectors on HEV system CAN circuit. For the removal of Li - ion battery controller, refer to DISASSEMBLY AND ASSEMBLY .
4. Check terminals and connectors for damage, bend and loose connection.
Is the inspection result normal?

YES

GO TO STEP 3 .

NO

Repair the terminal and connector.

CHECK HARNESS CONTINUITY (SHORT CIRCUIT)

Check the continuity between the data link connector terminals.

Data link connector			Continuity
Connector No.	Terminal No.
M25	13	12	Not existed

Is the inspection result normal?

YES

GO TO STEP 4 .

Check the harness and repair or replace [if shield line or fuse block (J/B) is short] the root cause.

CHECK HARNESS CONTINUITY (SHORT CIRCUIT)

Check the continuity between the data link connector and the ground.

Data link connector		Ground	Continuity
Connector No.	Terminal No.
M25	13		Not existed
	12		Not existed

Is the inspection result normal?

YES

GO TO STEP 5 .

Check the harness and repair or replace [if shield line or fuse block (J/B) is short] the root cause.

CHECK HARNESS CONTINUITY (SHORT CIRCUIT)

Check the continuity between the vehicle communication harness connector terminals. Refer to CIRCUIT DIAGRAM .

Vehicle communication harness (LB39)		Continuity
Terminal No.
3	15	Not existed

Is the inspection result normal?

YES

GO TO STEP 6 .

Repair the vehicle communication harness.

CHECK HARNESS CONTINUITY (SHORT CIRCUIT)

Check the continuity between the vehicle communication harness connector and the ground. Refer to CIRCUIT DIAGRAM .

Vehicle communication harness (LB39)	Ground	Continuity
Terminal No.		Continuity
3		Not existed
15		Not existed

Is the inspection result normal?

YES

GO TO STEP 7 .

Repair the vehicle communication harness.

CHECK ECM AND LI - ION BATTERY CONTROLLER TERMINATION CIRCUIT

Remove the ECM.

Check the resistance between the ECM terminals.

ECM		Resistance (Ω)
Terminal No.
55	54	Approx. 108 - 132

Remove the Li - ion battery controller. Refer to DISASSEMBLY AND ASSEMBLY .

Check the resistance between the Li - ion battery controller terminals.

Li - ion battery controller		Resistance (Ω)
Terminal No.
1	13	Approx. 108 - 132

Is the measurement value within the specification?

YES

GO TO STEP 8 .

Replace the ECM and/or the Li - ion battery controller.

CHECK SYMPTOM

Connect all the connectors. Check if the symptoms described in the "Symptom (Results from interview with customer) " are reproduced.

Inspection result

Reproduced

GO TO STEP 9 .

Non - reproduced

Start the diagnosis again. Follow the trouble diagnosis procedure when past error is detected.

CHECK CONTROL UNIT REPRODUCTION

Perform the reproduction test as per the following procedure for each control unit.
1. Turn the ignition switch OFF.
2. Disconnect the 12V battery cable from the negative terminal.
3. Disconnect one of the control unit connectors of HEV system CAN circuit.
  WARNING:
  Disconnect the high voltage when disconnecting the Li-ion battery connector (T28). Refer to HOW TO DISCONNECT HIGH VOLTAGE .
  
  NOTE:
  ECM and Li - ion battery controller have a termination circuit. Check other control units first.
4. Connect the 12V battery cable to the negative terminal. Check if the symptoms described in the "Symptom (Results from interview with customer) " are reproduced.
  NOTE:
  Although control unit-related error symptoms occur, do not confuse them with other symptoms.
Inspection result

Reproduced

Connect the connector. Check other control units as per the above procedure.

Non - reproduced

Replace the control unit whose connector was disconnected.