HandsFreeLink System Symptom Troubleshooting - HFL does not respond
HFL does not respond
NOTE:
Check the vehicle 12 volt 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 input check:

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

?2.
Go into the System Diagnostic Mode, and use the Knob Check in the Version/System to check the HFL switch.

Does all the HFL switch buttons respond?

     
YES
     
     
     
Go to step 2.
     
NO: With audio remote switch
     
     
     
Go to step 6.
     
NO: Without audio remote switch
     
     
     
Go to step 7.
2.
Bluetooth module check:

Bluetooth module check
?1.
Go into the System Diagnostic Mode, and use the Version Display in the Version/System to check the Bluetooth module.

Is the Bluetooth module version indicated?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
3.
In Line Diag check:

In Line Diag check
?1.
Go into the System Diagnostic Mode, and use the In Line Diag to check the microphone connection.

Does the HFT MIC indicate OK?

     
YES
     
     
     
Go to step 4.
     
NO
     
     
     
Go to step 13.
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 cell phone with Bluetooth to the customer's vehicle.

Can you pair the cell phone?

     
YES: USA models
     
     
     
     
YES: Except USA models
     
     
     
Go to step 5.
     
NO
     
     
     
5.
Cell phone connection check (customer's phone):

Cell phone connection check (customer's phone)
?1.
Pair the customer's cell phone with Bluetooth to the customer's vehicle.

Can you pair the cell phone, and does it operate normally?

     
YES
     
     
     
The HFL system is OK at this time. Inquire if there are any known issues for the problem.?
     
NO
     
     
     
The customer's cell phone is defective or not compatible.?
6.
Determine possible failure area (HFL switch circuit, others):

Determine possible failure area (HFL switch circuit, others)
?1.
Go into the System Diagnostic Mode, and use the Knob Check in the Version/System 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.
Disconnect the following connector.
HFL switch 7P connector

?3.
Do the HFL Switch Test.

Is the HFL switch OK?

     
YES
     
     
     
Go to step 8.
     
NO
     
     
     
8.
Shorted wire check (HFT/NAVI REMOTE SW line):

Shorted wire check (HFT/NAVI REMOTE SW line)
?1.
Disconnect the following connector.
NOTE: Eject the disc before disconnecting the audio unit to prevent damaging the CD player's load mechanism.

Audio unit connector A (24P)

?2.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
HFL switch 7P connector: disconnected
 
Audio unit connector A (24P): disconnected
Test point 1
Audio unit connector A (24P) No. 20
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short to body ground in the wire. If the wire is OK, replace the cable reel.?
     
NO
     
     
     
The HFT/NAVI REMOTE SW wire is not shorted to ground. Go to step 9.
9.
Determine possible failure area (audio unit, others):

Determine possible failure area (audio unit, others)
?1.
Reconnect the HFL switch 7P connector.

?2.
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
Test point 1
Audio unit connector A (24P) No. 19
Test point 2
Audio unit connector A (24P) No. 20

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
     
     
     
     
NO: With audio remote switch
     
     
     
Go to step 10.
     
NO: Without audio remote switch
     
     
     
Go to step 12.
10.
Determine possible failure area (HFT/NAVI REMOTE SW line, others):

Determine possible failure area (HFT/NAVI REMOTE SW line, others)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Audio unit connector A (24P): disconnected
Test point 1
Audio remote switch 12P connector No. 5 (female terminals):
Test point 2
HFL switch 7P connector No. 5 (female terminals):


Is there continuity?

     
YES
     
     
     
Repair an open in the wire. If the wire is OK, replace the cable reel.?
     
NO
     
     
     
The HFT/NAVI REMOTE SW wire is OK. Go to step 11.
11.
Audio remote switch check:

Audio remote switch check
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Audio unit connector A (24P): disconnected
Test point 1
Audio remote switch 12P connector No. 4 (female terminals):
Test point 2
Audio remote switch 12P connector No. 5 (female terminals):


Is there continuity?

     
YES
     
     
     
Repair an open in the wire.?
     
NO
     
     
     
12.
Open wire check (HFT/NAVI REMOTE SW line):

Open wire check (HFT/NAVI REMOTE SW line)
?1.
Disconnect the following connector.
HFL switch 7P connector

?2.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Audio unit connector A (24P): disconnected
 
HFL switch 7P connector: disconnected
Test point 1
Audio unit connector A (24P) No. 20
Test point 2
HFL switch 7P connector No. 3 (female terminals):


Is there continuity?

     
YES
     
     
     
Repair an open in the REMOTE SW GND/AUDIO GND wire. If the wire is OK, replace the cable reel.?
     
NO
     
     
     
Repair an open in the HFT/NAVI REMOTE SW wire. If the wire is OK, replace the cable reel.?
13.
Determine possible failure area (HFL microphone, others):

Determine possible failure area (HFL microphone, others)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
HFL microphone 3P connector

?3.
Turn the vehicle to the ON mode.

?4.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
 
HFL microphone 3P connector: disconnected
Test point 1
HFL microphone 3P connector No. 2 (female terminals):
Test point 2
HFL microphone 3P connector No. 3 (female terminals):


Is there about 8.0 V?

     
YES
     
     
     
     
NO
     
     
     
Go to step 14.
14.
Determine possible failure area (MIC+ line, others):

Determine possible failure area (MIC+ line, others)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
 
HFL microphone 3P connector: disconnected
Test point 1
HFL microphone 3P connector No. 3 (female terminals):
Test point 2
Body ground


Is there about 8.0 V?

     
YES
     
     
     
The MIC+ wire is OK. Go to step 18.
     
NO
     
     
     
Go to step 15.
15.
Open wire check (MIC+ line):

Open wire check (MIC+ line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
 
HFL microphone 3P connector: disconnected
Test point 1
Audio unit connector B (32P) No. 22
Test point 2
Body ground

Is there about 8.0 V?

     
YES
     
     
     
There is an open in the wire. Replace the affected shielded harness.?
     
NO
     
     
     
The MIC+ wire is not open. Go to step 16.
16.
Shorted wire check (MIC+ line):

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

?2.
Disconnect the following connector.
Audio unit connector B (32P)

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
HFL microphone 3P connector: disconnected
 
Audio unit connector B (32P): disconnected
Test point 1
Audio unit connector B (32P) No. 22
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
There is a short in the wire. Replace the affected shielded harness.?
     
NO
     
     
     
The MIC+ wire is not shorted to ground. Go to step 17.
17.
Shorted wire check (MIC+ line to another lines):

Shorted wire check (MIC+ line to another lines)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
HFL microphone 3P connector: disconnected
 
Audio unit connector B (32P): disconnected
Test point 1
Audio unit connector B (32P) No. 22
Test point 2
Audio unit connector B (32P) No. 6


Is there continuity?

     
YES
     
     
     
There is a short in the wires. Replace the affected shielded harness.?
     
NO
     
     
     
18.
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 B (32P)

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
HFL microphone 3P connector: disconnected
 
Audio unit connector B (32P): disconnected
Test point 1
HFL microphone 3P connector No. 2 (female terminals):
Test point 2
Audio unit connector B (32P) No. 23


Is there continuity?

     
YES
     
     
     
     
NO
     
     
     
There is an open in the wire. Replace the affected shielded harness.?