Diagnosis and Repair Workflow

BASIC INSPECTION

DIAGNOSIS AND REPAIR WORKFLOW

Information Needed for Trouble Diagnosis
HEV SYSTEM CAN performs trouble diagnosis with the following tools.






Trouble Diagnosis Flow Chart

Trouble Diagnosis Flow Chart:

Trouble Diagnosis Procedure

CHECK VEHICLE CONDITION
Check whether or not the DTC related to HEV SYSTEM CAN indicated on All DTC Reading by CONSULT-III.

NOTE: Root cause cannot be detected using the procedure if the DTC related to HEV SYSTEM CAN is not indicated. Refer to "DTC Related To HEV System CAN List", chart below.

OUTPUT OF DATA
Print out or save All DTC Reading.

CREATE DIAGNOSIS SHEET
Print out diagnosis sheet. Refer to "Diagnosis Sheet, below".

NOTE: For abbreviations, refer to "Abbreviation List". Abbreviation List






DETECT THE ROOT CAUSE

Description
To detect the root cause of HEV SYSTEM CAN, check for short circuit first. When there is no short circuit, check for open circuit.

Short Circuit
Check for short circuit, and DLC branch line open circuit.
When the symptoms listed below exist, a short circuit of the HEV SYSTEM CAN communication line or control unit is a possible cause.






Error symptom
- Most the units connected to the HEV SYSTEM CAN go into fail-safe mode or are deactivated.

Inspection procedure
- Refer to "Short Circuit". Malfunction Area Chart






NOTE: DLC branch line circuit can be open when the following conditions are satisfied as All DTC Reading result;
- The DTCs related to HEV SYSTEM CAN are not displayed as ENGINE or HYBRID SYSTEM item.
- The items of EPS and ABS are not displayed.

For the DLC branch line circuit inspection procedure, refer to "Branch Line". Malfunction Area Chart

Open Circuit
Draw a line on the diagnosis sheet to indicate the possible cause. Narrow the search.

NOTE:
- Color-code when drawing lines.
- Do not draw a line onto a existing line.
- When the root cause appears to be a branch line, be sure to check the control unit as well as the communication line.

1. Check each item on the printed or saved All DTC Reading. Draw a line on the diagnosis sheet to indicate the error circuit. Refer to "DTC Related To HEV System CAN List", chart below.

a. Reception item of HYBRID SYSTEM:
i. U0100:LOST COMM [ECM]:211, "U0100:LOST COMM [ECM]:212" and U0100:LOST COMM [ECM]:530" are indicated. This means HV ECU cannot receive the signal from ECM. Draw a line to indicate an error between HV ECU and ECM (line 1-a-i in the figure below).
ii. "U0131:LOST COMM [EPS]:433" and "U0131:LOST COMM [EPS]:434" are indicated. This means HV ECU cannot receive the signal from EPS. Draw a line to indicate an error between HV ECU and EPS (line 1-a-ii in the figure below).






b. Reception item of "ENGINE":
i. U0293 and U1020 are indicated. This means ECM cannot receive the signal from HV ECU. Draw a line to indicate an error between ECM and HV ECU (line 1-b-i in the figure below).
ii. "U0129 and U1022" are indicated. This means ECM cannot receive the signal from ABS. Draw a line to indicate an error between ECM and ABS (line 1-b-ii in the figure below).






2. Based on information received from the printed or saved All DTC Reading, place a check mark on the known good HEV SYSTEM CAN communication line between ECM and HV ECU.
a. Through the previous procedure, the circuit between EPS splice and ABS splice has the most amount of lines (shade 2-a in the figure below).
b. Place a check mark on the known good lines to establish the error circuit.
Reception item of ABS: "U0073", "U0123" and "U0124" are not indicated. ABS communicates normally with YAW. Put a check mark on the normal circuit between ABS and YAW (check mark 2-b in the figure below).






3. Through the above procedure, the error is detected in between EPS and DLC main line (shaded in the figure below).

NOTE: For abbreviations, refer to Information Bus Abbreviation List.

4. Perform the inspection for the detected error circuit. For the inspection procedure, refer to "Main Line". Malfunction Area Chart (When the error is detected on branch line, refer to "Branch Line". Malfunction Area Chart.)






Diagnosis Sheet

Diagnosis Sheet:

DTC Related to HEV SYSTEM CAN List

DTC Related To HEV System CAN List (Part 1):

DTC Related To HEV System CAN List (Part 2):

DTC Related To HEV System CAN List (Part 3):