How to Check the Telematics Control Unit Status

NOTE: 

• Check the vehicle 12 volt battery condition first - Refer to: 12 Volt Battery Test (Without SH-AWD) or 12 Volt Battery Test (With SH-AWD) .
• The self-diagnostic function starts after you press and hold the HANG-UP/BACK button on the audio remote-HFL switch for 5 seconds, and ends if the telematics control unit returns to its idle state.

1. Turn the vehicle to the ON mode

2. Press and hold the HANG-UP/BACK button (A) for more than 5 seconds, and self-diagnostic function begins.

Courtesy of HONDA, U.S.A., INC.

3. When the telematics control unit enters the self-diagnostic function, the following will occurs:

• While in diagnosis, the AcuraLink system status indicator is blinks green and red alternately.
• If the telematics control unit does not respond, go to AcuraLink services do not work troubleshooting - Refer to: AcuraLink Symptom Troubleshooting - AcuraLink services do not work,  or AcuraLink Symptom Troubleshooting - AcuraLink system status indicator does not come on .
• If the telematics control unit is OK, and there are no telematics DTCs, the telematics control unit says, "The TCU is OK."
• If there are any telematics system DTCs stored, the telematics control unit says, "The following failure is detected - (detected DTC's description)." Check for telematics system DTCs .