Operation Procedure

WARNING: This page is about a different car, the 2006 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.

Start the engine.
Turn the audio system off.
While pressing the "4" button, turn the volume control dial clockwise or counterclockwise for 30 clicks or more. (When the self-diagnosis mode is started, a short beep will be heard.)

Fig 1: Turning Volume Control Dial Clockwise Or Counterclockwise
Courtesy of NISSAN MOTOR CO., U.S.A.
The initial trouble diagnosis screen will be shown, and items "Self-Diagnosis (DCU)", "Self-Diagnosis (NAVI)", "Confirmation/Adjustment" and "CAN DIAG SUPPORT MONITOR" will become selective.
Select "CAN DIAG SUPPORT MONITOR".

Fig 2: Displaying Self-Diagnosis (NAVI) Screen
Courtesy of NISSAN MOTOR CO., U.S.A.

Display status of CAN communication.

ITEM CONSTANT

Item	Content	Error counter
CAN_COMM	OK/NG	0-50
CAN_CIRC_1	OK/UNKWN	0-50
CAN_CIRC_2	OK/UNKWN	0-50
CAN_CIRC_3	OK/UNKWN	0-50
CAN_CIRC_4	OK/UNKWN	0-50
CAN_CIRC_5	OK/UNKWN	0-50
CAN_CIRC_6	OK/UNKWN	0-50
CAN_CIRC_7	OK/UNKWN	0-50
CAN_CIRC_8	OK/UNKWN	0-50
CAN_CIRC_9	OK/UNKWN	0-50

Fig 3: Displaying Self-Diagnosis Screen - CAN DIAG SUPPORT MONITOR

Courtesy of NISSAN MOTOR CO., U.S.A.

If the ignition is turned on and UNKWN is shown on the screen, the value of the counter will be up. (MAX50)
The value of the counter does not change if the ignition changes to OFF. (MAX50)
If the counter shows the value of 50 and UNKWN is shown, the value of 50 will not be changed.