LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Infiniti >> 2012 >> G25 Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 9 (LAN System) >> [Can Fundamental] >> System Description >> Trouble Diagnosis >> Symptom When Error Occurs in CAN Communication System >> Error Example
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Error Example

WARNING: This page is about a different car, the 2011 Nissan Leaf. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Each vehicle differs in symptom of each control unit under fail-safe mode and CAN communication line wiring.
Example: Main Line Between Data Link Connector and ABS Actuator and Electric Unit (Control Unit) Open Circuit
Fig 1: Main Line Between Data Link Connector And ABS Actuator And Electric Unit (Control Unit) Open Circuit Diagram
G06934907Courtesy of NISSAN MOTOR CO., U.S.A.
SYMPTOM CHART

Unit name Major symptom
ECM Engine torque limiting is affected, and shift harshness increases.
BCM
  • Reverse warning buzzer does not sound.
  • The front wiper moves under continuous operation mode even though the front wiper switch being in the intermittent position.
EPS control unit The steering effort increases.
Combination meter
  • The shift position indicator and OD OFF indicator turn OFF.
  • The speedometer is inoperative.
  • The ODO/TRIP METER stops.
ABS actuator and electric unit (control unit) Normal operation.
TCM No impact on operation.
IPDM E/R When the ignition switch is ON,
  • The headlamps (Lo) turn ON.
  • The cooling fan continues to rotate.

Example: TCM Branch Line Open Circuit

Fig 2: TCM Branch Line Open Circuit Diagram
G06934908Courtesy of NISSAN MOTOR CO., U.S.A.
SYMPTOM CHART

Unit name Major symptom
ECM Engine torque limiting is affected, and shift harshness increases.
BCM Reverse warning buzzer does not sound.
EPS control unit Normal operation.
Combination meter
  • Shift position indicator and O/D OFF indicator turn OFF.
  • Warning lamps turn ON.
ABS actuator and electric unit (control unit) Normal operation.
TCM No impact on operation.
IPDM E/R Normal operation.
NOTE: The model (all control units on CAN communication system are Diag on CAN) cannot perform CAN diagnosis with CONSULT if the following error occurs. The error is judged by the symptom.
ERROR REFERENCE CHART

Error Difference of symptom
Data link connector branch line open circuit Normal operation.
CAN-H, CAN-L harness short-circuit Most of the control units which are connected to the CAN communication system enter fail-safe mode or are deactivated.

Example: Data Link Connector Branch Line Open Circuit

Fig 3: Data Link Connector Branch Line Open Circuit Diagram
G06934909Courtesy of NISSAN MOTOR CO., U.S.A.
SYMPTOM CHART

Unit name Major symptom
ECM Normal operation.
BCM
EPS control unit
Combination meter
ABS actuator and electric unit (control unit)
TCM
IPDM E/R
NOTE: When data link connector branch line is open, transmission and reception of CAN communication signals are not affected. Therefore, no symptoms occur. However, be sure to repair malfunctioning circuit.

Example: CAN-H, CAN-L Harness Short Circuit

Fig 4: CAN-H, CAN-L Harness Short Circuit Diagram
G06934910Courtesy of NISSAN MOTOR CO., U.S.A.
SYMPTOM CHART

Unit name Major symptom
ECM
  • Engine torque limiting is affected, and shift harshness increases.
  • Engine speed drops.
BCM
  • Reverse warning buzzer does not sound.
  • The front wiper moves under continuous operation mode even though the front wiper switch being in the intermittent position.
  • The room lamp does not turn ON.
  • The engine does not start (if an error or malfunction occurs while turning the ignition switch OFF.)
  • The steering lock does not release (if an error or malfunction occurs while turning the ignition switch OFF.)
EPS control unit The steering effort increases.
Combination meter
  • The tachometer and the speedometer do not move.
  • Warning lamps turn ON.
  • Indicator lamps do not turn ON.
ABS actuator and electric unit (control unit) Normal operation.
TCM No impact on operation.
IPDM E/R When the ignition switch is ON,
  • The headlamps (Lo) turn ON.
  • The cooling fan continues to rotate.
scientia non olet · About LEMON Manuals