Audio remote switch does not work properly (with navigation)

WARNING: This page is about a different car, the 2011 Acura TL, 2010 Acura TL, and 2009 Acura TL. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

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

Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
Turn on the audio-navigation unit, and check the audio remote switch operation (volume up, volume down, CH (UP), CH (DOWN), MODE)
Is the audio system operation OK?

YES -Intermittent failure, the audio remote switch is OK at this time Check for loose connections

NO -Go to step 3
Test the audio remote switch (see Audio Remote Switch Test )
Is the audio remote switch OK?

YES -Go to step 4

NO -Replace the audio remote, HFL-navigation voice control switch (see STEERING WHEEL DISASSEMBLY/REASSEMBLY )
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
Remove the audio-navigation unit (see AUDIO-NAVIGATION UNIT REMOVAL/INSTALLATION )
Disconnect audio-navigation unit connector A (24P)
NOTE: Eject all the CDs before disconnecting audio-navigation unit to prevent damaging the CD player's load mechanism

Reconnect the audio remote switch, and measure the resistance between audio-navigation unit connector A (24P) terminals No 5 and No 16 as specified in the table

Fig 1: Measuring Resistance Between Audio-Navigation Unit Connector A (24P) Terminals No 5 And No 16

Courtesy of AMERICAN HONDA MOTOR CO., INC.

AUDIO REMOTE SWITCH TABLE

AUDIO REMOTE SWITCH REFERENCE CHART

Button held down	VOL DOWN	VOL UP	CH (-)	CH (+)	MODE	No button pressed
Resistance	about 100 Ω	about 357 Ω	about 775 Ω	about 1.7 kΩ	about 3.7 kΩ	about 10 kΩ

Is the resistance OK?

YES -Go to step 8

NO -Repair short or high resistance in the circuit between the audio-navigation unit and the audio remote switch If the wires are OK, replace the cable reel (see DISPOSAL OF DAMAGED COMPONENTS )

Disconnect the audio remote, HFL-navigation voice control switch 12P connector
Check for continuity between body ground and terminals No 5 and No 16 of audio-navigation unit connector A (24P) individually

Fig 2: Checking Continuity Between Body Ground And Terminals No 5 And No 16 Of Audio-Navigation Unit Connector A (24P)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair short to body ground in the circuit between the audio-navigation unit and the audio remote switch If the wires are OK, replace the cable reel (see CABLE REEL REPLACEMENT )

NO -Replace the audio-navigation unit (see AUDIO-NAVIGATION UNIT REMOVAL/INSTALLATION )