Condition of Error Detection
DTC (e.g. U1000 and U1001) of CAN communication is indicated on SELF-DIAG RESULTS on CONSULT-III if a CAN communication signal is not transmitted or received between units for 2 seconds or more.
CAN COMMUNICATION SYSTEM ERROR
- CAN communication line open (CAN-H, CAN-L, or both)
- CAN communication line short (ground, between CAN communication lines, other harnesses)
- Error of CAN communication control circuit of the unit connected to CAN communication line
WHEN DTC OF CAN COMMUNICATION IS INDICATED EVEN THOUGH CAN COMMUNICATION SYSTEM IS NORMAL
- Removal/installation of parts: Error may be detected when removing and installing CAN communication unit and related parts while turning the ignition switch ON. (A DTC except for CAN communication may be detected.)
- Fuse blown out (removed): CAN communication of the unit may cease.
- Voltage drop: Error may be detected if voltage drops due to discharged battery when turning the ignition switch ON (Depending on the control unit which carries out CAN communication).
- Error may be detected if the power supply circuit of the control unit, which carries out CAN communication, malfunctions (Depending on the control unit which carries out CAN communication).
- Error may be detected if reprogramming is not completed normally.
| CAUTION | CAN communication system is normal if DTC of CAN communication is indicated on SELF-DIAG RESULTS of CONSULT-III under the above conditions. Erase the memory of the self-diagnosis of each unit. |
MONITOR ITEM (CONSULT-III)
Example: CAN DIAG SUPPORT MNTR indication
Scheme 15
Without PAST
| Item | PRSNT | Description |
|---|---|---|
| Initial diagnosis | OK | Normal at present |
| NG | Control unit error (Except for some control units) | |
| Transmission diagnosis | OK | Normal at present |
| UNKWN | Unable to transmit signals for 2 seconds or more. | |
| Diagnosis not performed | ||
| Control unit name (Reception diagnosis) | OK | Normal at present |
| UNKWN | Unable to receive signals for 2 seconds or more. | |
| Diagnosis not performed | ||
| No control unit for receiving signals. (No applicable optional parts) |
CAN DIAGNOSTIC SUPPORT MONITOR DESCRIPTION CHART - WITHOUT PAST
With PAST
| Item | PRSNT | PAST | Description |
|---|---|---|---|
| Transmission diagnosis | OK | OK | Normal at present and in the past |
| 1 - 39 | Normal at present, but unable to transmit signals for 2 seconds or more in the past. (The number indicates the number of ignition switch cycles from OFF to ON.) | ||
| UNKWN | 0 | Unable to transmit signals for 2 seconds or more at present. | |
| Control unit name (Reception diagnosis) | OK | OK | Normal at present and in the past |
| 1 - 39 | Normal at present, but unable to receive signals for 2 seconds or more in the past. (The number indicates the number of ignition switch cycles from OFF to ON.) | ||
| UNKWN | 0 | Unable to receive signals for 2 seconds or more at present. | |
| Diagnosis not performed. | |||
| No control unit for receiving signals. (No applicable optional parts) |
CAN DIAGNOSTIC SUPPORT MONITOR DESCRIPTION CHART - WITH PAST
How to Use CAN Communication Signal Chart
The CAN communication signal chart lists the signals needed for trouble diagnosis. It is useful for detecting the root cause by finding a signal related to the symptom, and by checking transmission and reception unit.
Scheme 16
Scheme 17
INTERVIEW WITH CUSTOMER
Interview with the customer is important to detect the root cause of CAN communication system errors and to understand vehicle condition and symptoms for proper trouble diagnosis.
Points in interview
- What: Parts name, system name
- When: Date, Frequency
- Where: Road condition, Place
- In what condition: Driving condition/environment
- Result: Symptom
Note. Check normal units as well as error symptoms. Example: Circuit between ECM and the combination meter is judged normal if the customer indicates tachometer functions normally. When a CAN communication system error is present, multiple control units may malfunction or go into fail-safe mode. Indication of the combination meter is important to detect the root cause because it is the most obvious to the customer, and it performs CAN communication with many units.
Scheme 18
CREATE INTERVIEW SHEET
Fill out the symptom described by the customer, vehicle condition, and CAN system type on the interview sheet.
Interview Sheet (Example)
Scheme 19
DETECT THE ROOT CAUSE
CAN diagnosis function of CONSULT-III detects the root cause.
Caution
- This information describes information peculiar to a vehicle and inspection procedures.
- For trouble diagnosis procedure, refer to " «TROUBLE DIAGNOSIS PROCEDURE»(ref-405854-S22456339702011062300000) ".
FOR USA AND CANADA : Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT PRE-TENSIONER"
The Supplemental Restraint System such as "AIR BAG" and "SEAT BELT PRE-TENSIONER", used along with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the "SRS AIR BAG" and "SEAT BELT" of this Service Information.
| WARNING | To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death in the event of a collision that would result in air bag inflation, all maintenance must be performed by an authorized NISSAN/INFINITI dealer. Improper maintenance, including incorrect removal and installation of the SRS, can lead to personal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air Bag Module, see the SRS AIR BAG article. Never use electrical test equipment on any circuit related to the SRS unless instructed to in this Service Information. SRS wiring harnesses can be identified by yellow and/or orange harnesses or harness connectors. |
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
| WARNING | When working near the Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the ignition ON or engine running, never use air or electric power tools or strike near the sensor(s) with a hammer. Heavy vibration could activate the sensor(s) and deploy the air bag(s), possibly causing serious injury. When using air or electric power tools or hammers, always switch the ignition OFF, disconnect the battery, and wait at least 3 minutes before performing any service. |
FOR MEXICO : Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT PRE-TENSIONER"
The Supplemental Restraint System such as "AIR BAG" and "SEAT BELT PRE-TENSIONER", used along with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of collision. Information necessary to service the system safely is included in the "SRS AIR BAG" and "SEAT BELT" of this Service Information.
| WARNING | To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death in the event of a collision which would result in air bag inflation, all maintenance must be performed by an authorized NISSAN/INFINITI dealer. Improper maintenance, including incorrect removal and installation of the SRS, can lead to personal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air Bag Module, see the SRS AIR BAG article. Never use electrical test equipment on any circuit related to the SRS unless instructed to in this Service Information. SRS wiring harnesses can be identified by yellow and/or orange harnesses or harness connectors. |
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
| WARNING | When working near the Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the ignition ON or engine running, never use air or electric power tools or strike near the sensor(s) with a hammer. Heavy vibration could activate the sensor(s) and deploy the air bag(s), possibly causing serious injury. When using air or electric power tools or hammers, always switch the ignition OFF, disconnect the battery, and wait at least 3 minutes before performing any service. |
CAN Communication Signal Chart
Refer to " HOW TO USE CAN COMMUNICATION SIGNAL CHART " for how to use CAN communication signal chart.
Note. Refer to " ABBREVIATION LIST " for the abbreviations of the connecting units.
Scheme 20
Scheme 21
Scheme 22
Note. CAN data of the air bag diagnosis sensor unit is not used by usual service work, thus it is omitted.
Scheme 23
Scheme 24
Scheme 25
Scheme 26
Scheme 27
Scheme 28
Main Line
| Malfunction area | Reference |
|---|---|
| Main line between BCM and data link connector | " DIAGNOSIS PROCEDURE " |
| Main line between data link connector and TCM | " DIAGNOSIS PROCEDURE " |
MALFUNCTION AREA CHART - MAIN LINE
Branch Line
| Malfunction area | Reference |
|---|---|
| ECM branch line circuit | " DIAGNOSIS PROCEDURE " |
| AWD control unit branch line circuit | " DIAGNOSIS PROCEDURE " |
| Air bag diagnosis sensor unit branch line circuit | " DIAGNOSIS PROCEDURE " |
| BCM branch line circuit | " DIAGNOSIS PROCEDURE " |
| Intelligent Key unit branch line circuit | " DIAGNOSIS PROCEDURE " |
| Steering angle sensor branch line circuit | " DIAGNOSIS PROCEDURE " |
| Data link connector branch line circuit | " DIAGNOSIS PROCEDURE " |
| EPS control unit branch line circuit | " DIAGNOSIS PROCEDURE " |
| Combination meter branch line circuit | " DIAGNOSIS PROCEDURE " |
| ABS actuator and electric unit (control unit) branch line circuit | " DIAGNOSIS PROCEDURE " |
| TCM branch line circuit | " DIAGNOSIS PROCEDURE " |
| IPDM E/R branch line circuit | " DIAGNOSIS PROCEDURE " |
MALFUNCTION AREA CHART - BRANCH LINE
Short Circuit
| Malfunction area | Reference |
|---|---|
| CAN communication circuit | " DIAGNOSIS PROCEDURE " |
MALFUNCTION AREA CHART - SHORT CIRCUIT