Display Unit Buttons Do Not Work

NOTE: Always check all of the connectors for loose terminals.

Turn the ignition switch to ACC (I).
Measure the voltage between body ground and display unit connector B (20P) terminals No. 1 and No. 2 individually.

Fig 1: Measuring Voltage
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?
1. YES -Go to step 3.
2. NO -If the RED/YEL wire does not have voltage, repair the open in the wire between the passenger's under-dash fuse/relay box and the display unit. If the YEL/BLK wire does not have voltage, repair the open in the wire between the driver's underdash fuse/relay box and the display unit.
Check for continuity between display unit connector B (20P) terminal No. 10 and body ground.

Fig 2: Checking Continuity At Display Unit Connector B (20P)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES -Go to step 4.
2. NO -Repair the open in the wire between the display unit and body ground (G501).
Turn the ignition switch OFF.
Disconnect the navigation unit and display unit connectors.
Check for continuity between body ground and display unit connector B (20P) terminals No. 5 and No. 15 individually.

Fig 3: Checking Continuity At Display Unit Connector B (20P)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES -There is a short to body ground in the circuit between the display unit and the navigation unit. Replace the affected shielded harness.
2. NO -Go to step 7.
Check for continuity between display unit connector B (20P) terminal No. 5 and navigation unit connector B (16P) terminal No. 7.

Fig 4: Checking Continuity At Display Unit Connector B (20P)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES -Go to step 8.
2. NO -There is an open in the circuit between the display unit and the navigation unit. Replace the affected shielded harness.
Check for continuity between display unit connector B (20P) terminal No. 15 and navigtion unit 16P connector B (16P) terminal No. 15.

Fig 5: Checking Continuity At Display Unit Connector B (20P)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES -Replace the display unit (see DISPLAY UNIT REMOVAL/INSTALLATION ).
2. NO -There is an open in the circuit between the display unit and the navigation unit. Replace the affected shielded harness.