Audio-navigation unit power switch will not turn on (No information display and no sound) (with navigation)

NOTE:

Check the vehicle battery condition first (see 12 VOLT BATTERY TEST ).
Check the connectors for poor connections or loose terminals.

Turn the ignition switch to ON (II).
Press the power button on to see if the audio-navigation unit turns on.
Does the audio-navigation unit display operate properly, and does the audio-navigation unit sound normal?

YES -Intermittent failure, the system is OK at this time.

NO -Go to step 3.
Turn the ignition switch to LOCK (0).
Check the No. B1 (15 A) fuse and the No. B14 (7.5 A) fuse in the under-dash fuse/relay box.
Are the fuses OK?

YES -Go to step 5.

NO -Replace the fuse(s), and recheck.
Remove the audio-navigation unit (see AUDIO-NAVIGATION UNIT REMOVAL/INSTALLATION ). Check that the audio-navigation unit is properly connected.
NOTE:
- Eject all the audio discs before removing the audio-navigation unit to prevent damaging the CD player's load mechanism.
- Remove the PC card before removing the audio-navigation unit.
Is it connected properly?

YES -Go to step 6.

NO -Repair poor connections and reconnect the connector(s), and recheck the function.
Turn the ignition switch to ON (II).
Measure the voltage between body ground and audio-navigation unit connector A (24P) terminals No. 3 and No. 24 individually, and between audio-navigation unit connector C (8P) terminal No. 4 and body ground.

Fig 1: Measuring Voltage Between Body Ground And Audio-Navigation Unit Connector A (24P) Terminals No. 3 And 24
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 2: Measuring Voltage Between Audio-Navigation Unit Connector C (8P) Terminal No. 4 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage on the these terminals?

YES -Go to step 8.

NO -Repair an open in the wire(s) between the No. B1 (15 A) fuse and/or the No. B14 (7.5 A) fuse in the under-dash fuse/relay box and the audio-navigation unit.
Measure the voltage between audio-navigation unit connector A (24P) terminal No. 1 and body ground, and between audio-navigation unit connector C (8P) terminal No. 1 and body ground.

Fig 3: Measuring Voltage Between Audio-Navigation Unit Connector A (24P) Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 4: Measuring Voltage Between Audio-Navigation Unit Connector C (8P) Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 0.2 V?

YES -Substitute a known-good audio-navigation unit (see AUDIO-NAVIGATION UNIT REMOVAL/INSTALLATION ), and recheck. If the symptom/indication goes away, replace the original audio-navigation unit (see AUDIO-NAVIGATION UNIT REMOVAL/INSTALLATION ).

NO -Repair an open or high resistance in the wire between the audio-navigation unit connector A (24P) terminal No. 1 or audio-navigation unit connector C (8P) terminal No. 1 and body ground (G503) (see DASHBOARD WIRE HARNESS (VIEW OF MIDDLE SECTION) (BD) ).