HandsFreeLink System Symptom Troubleshooting - HFL does not respond
HFL does not respond
NOTE:
Check the vehicle battery condition first.
You must be able to duplicate the customer's concern to successfully diagnose the problem. If you cannot duplicate the issue, have the customer demonstrate it.
Check the connectors for poor connections or loose terminals.
1.
HFL switch operation check:

HFL switch operation check
?1.
Turn the vehicle to the ON mode.

?2.
Go into the System Diagnostic Mode, and use the Hard Key to check the HFL switch.

Does all the HFL switch buttons respond?

     
YES
     
     
     
Go to step 2.
     
NO
     
     
     
Go to step 6.
2.
Bluetooth module check:

Bluetooth module check
?1.
Go into the System Diagnostic Mode, and use the HFT to check the Bluetooth Connection Diagnosis result.

Does the status indicate OK?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
Go to step 5.
3.
Microphone operation check:

Microphone operation check
?1.
Go into the System Diagnostic Mode, and use the Mic to check the microphone.

?2.
Press the TALK button, then say ‘‘testing’’ in front of the microphone to check the Mic level.

Is the microphone level OK?

     
YES
     
     
     
Go to step 4.
     
NO
     
     
     
Go to step 12.
4.
Cell phone connection check (known-good phone):

Cell phone connection check (known-good phone)
?1.
Turn the vehicle to the OFF (LOCK) mode then the ON mode.

?2.
Pair a known-good Bluetooth cell phone to the customer's vehicle.

Can you pair the Bluetooth cell phone?

     
YES
     
     
     
     
NO
     
     
     
Go to step 5.
5.
Audio panel check (substitution):

Audio panel check (substitution)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Substitute a known-good audio panel, and recheck.

Does the symptom go away?

     
YES
     
     
     
     
NO
     
     
     
6.
Determine possible failure area (Audio remote switch circuit, others):

Determine possible failure area (Audio remote switch circuit, others):
?1.
Go into the System Diagnostic Mode, and use the Hard Key to check the audio remote switch.

Does all the audio remote switch buttons respond?

     
YES
     
     
     
Go to step 7.
     
NO
     
     
     
7.
HFL switch check:

HFL switch check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Do the HFL Switch Test.

Is the HFL-navigation voice control switch OK?

     
YES
     
     
     
Go to step 8.
     
NO
     
     
     
8.
Determine possible failure area (Audio unit, others):

Determine possible failure area (Audio unit, others)
?1.
Reconnect the HFL switch 6P connector.

?2.
Disconnect the following connectors.
Audio unit connector A (24P)
Audio unit connector B (20P)

?3.
Measure the resistance between test points 1 and 2 as specified in the table.
Test condition
Vehicle OFF (LOCK) mode
 
Audio unit connector A (24P): disconnected
 
Audio unit connector B (20P): disconnected
Test point 1
Audio unit connector A (24P) No. 11
Test point 2
Audio unit connector B (20P) No. 12

Button held down
HANG-UP/BACK
PICK-UP
TALK
No button pressed
Resistance
About 47 ?
About 222 ?
About 2.25 k?
About 10 k?

Is the resistance OK?

     
YES
     
     
     
Go to step 9.
     
NO
     
     
     
Go to step 10.
9.
Audio unit check (HFT/NAVI REMOTE SW line):

Audio unit check (HFT/NAVI REMOTE SW line)
?1.
Disconnect the following connector.
HFL switch 6P connector

?2.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
HFL switch 6P connector: disconnected
 
Audio unit connector B (20P): disconnected
Test point 1
Audio unit connector B (20P) No. 12
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short to body ground in the wire between the audio unit and the HFL switch. If the wire is OK, replace the cable reel.?
     
NO
     
     
     
10.
Open wire check (HFT/NAVI REMOTE SW line):

Open wire check (HFT/NAVI REMOTE SW line)
?1.
Disconnect the following connector.
HFL switch 6P connector

?2.
Check for continuity between test points 1 and 2.
Without heated steering wheel
Test condition
Vehicle OFF (LOCK) mode
 
Audio unit connector B (20P): disconnected
 
HFL switch 6P connector: disconnected
Test point 1
Audio unit connector B (20P) No. 12
Test point 2
HFL switch 6P connector No. 3


Is there continuity?

     
YES
     
     
     
The HFT/NAVI REMOTE SW wire is OK. Go to step 11.
     
NO
     
     
     
Repair an open in the wire between the audio unit and the HFL switch. If the wire is OK, replace the cable reel.?
11.
Open wire check (AUDIO REMOTE GND line):

Open wire check (AUDIO REMOTE GND line)
?1.
Disconnect the following connector.
Audio remote switch 12P connector

?2.
Check for continuity between test points 1 and 2.
Without heated steering wheel
Test condition
Vehicle OFF (LOCK) mode
 
Audio remote switch 12P connector: disconnected
 
HFL switch 6P connector: disconnected
Test point 1
Audio remote switch 12P connector No. 4
Test point 2
HFL switch 6P connector No. 4


Is there continuity?

     
YES
     
     
     
     
NO
     
     
     
Repair an open in the wire between the audio remote switch and the HFL switch.?
12.
Determine possible failure area (MIC+ line, others):

Determine possible failure area (MIC+ line, others)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
Front HFL-ANC/active sound control microphone 8P connector

?3.
Turn the vehicle to the ON mode.

?4.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
 
Front HFL-ANC/active sound control microphone 8P connector: disconnected
Test point 1
Front HFL-ANC/active sound control microphone 8P connector No. 1
Test point 2
Front HFL-ANC/active sound control microphone 8P connector No. 2

Is there about 8.0 V?

     
YES
     
     
     
Go to step 13.
     
NO
     
     
     
Go to step 17.
13.
Open wire check (MIC+ line):

Open wire check (MIC+ line)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
Audio unit connector J (28P)

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Front HFL-ANC/active sound control microphone 8P connector: disconnected
 
Audio unit connector J (28P): disconnected
Test point 1
Front HFL-ANC/active sound control microphone 8P connector No. 2
Test point 2
Audio unit connector J (28P) No. 11

Is there continuity?

     
YES
     
     
     
The MIC+ wire is not open. Go to step 14.
     
NO
     
     
     
There is an open in the wire between the front HFL-ANC/active sound control microphone and the audio unit. Replace the affected shielded harness.?
14.
Shorted wire check (MIC+ line):

Shorted wire check (MIC+ line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Front HFL-ANC/active sound control microphone 8P connector: disconnected
 
Audio unit connector J (28P): disconnected
Test point 1
Audio unit connector J (28P) No. 11
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
There is a short to body ground in the wire between the front HFL-ANC/active sound control microphone and the audio unit. Replace the affected shielded harness.?
     
NO
     
     
     
The MIC+ wire is not shorted. Go to step 15.
15.
Shorted wire check (MIC+ line to MIC? line, SH MIC line):

Shorted wire check (MIC+ line to MIC? line, SH MIC line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Front HFL-ANC/active sound control microphone 8P connector: disconnected
 
Audio unit connector J (28P): disconnected
Test circuit 1
  
Test point 1
Audio unit connector J (28P) No. 10
Test point 2
Audio unit connector J (28P) No. 11

Test circuit 2
  
Test point 1
Audio unit connector J (28P) No. 11
Test point 2
Audio unit connector J (28P) No. 12

Is there continuity?

     
YES
     
     
     
There is a short in the wires between the front HFL-ANC/active sound control microphone and the audio unit. Replace the affected shielded harness.?
     
NO
     
     
     
The MIC+ wire is OK. Go to step 16.
16.
Microphone check (substitution):

Microphone check (substitution)
?1.
Substitute a known-good front HFL-ANC/active sound control microphone, and recheck.

Does the symptom go away?

     
YES
     
     
     
     
NO
     
     
     
17.
Determine possible failure area (MIC PWR line, MIC? line):

Determine possible failure area (MIC PWR line, MIC? line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
 
Front HFL-ANC/active sound control microphone 8P connector: disconnected
Test point 1
Front HFL-ANC/active sound control microphone 8P connector No. 4
Test point 2
Body ground

Is there about 8.0 V?

     
YES
     
     
     
There is an open in the wire between the front HFL-ANC/active sound control microphone and the audio unit. Replace the affected shielded harness.?
     
NO
     
     
     
Go to step 18.
18.
Open wire check (MIC PWR line):

Open wire check (MIC PWR line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
 
Front HFL-ANC/active sound control microphone 8P connector: disconnected
Test point 1
Audio unit connector J (28P) No. 25
Test point 2
Body ground

Is there about 8.0 V?

     
YES
     
     
     
Repair an open in the wire between the front HFL-ANC/active sound control microphone and the audio unit.?
     
NO