Buick Regal: Auxiliary Audio Input Malfunction (IO5/IO6)

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Refer to Diagnostic Procedure Instructions provide an overview of each diagnostic category.

Diagnostic Fault Information

1. SD Card reader and/or USB port (s) Inoperative
2. No left side audio from device connected to AUX jack
3. No right side audio from device connected to AUX jack
4. Noticeable distortion may be present in affected audio channel
5. Fault may affect one or more components, dependent on fault location
6. Fault affects multiple components, dependent on vehicle equipment
7. Radio does not detect auxiliary device connection, AUX not available as input selection
8. AUX always available as an input selection, with or without auxiliary device connected
9. Console USB ports inoperative

Circuit/System Description

The infotainment system has a auxiliary jack, USB, and memory card receptacle assembly located in the armrest compartment. The two USB ports and the card reader slot interface with a hub device, internal to the assembly. The assembly receives fused battery voltage and ground from the harness to power the internal hub device as well as providing additional amperage to power USB devices.

The internal hub device interfaces directly with the human machine interface control module via a standard USB cable. A Mini type USB connector is used to connect the cable at the human machine interface control module and at the auxiliary jack, USB, and memory card receptacle assembly. Standard USB male to female connections are typically used for connecting USB cables together where an in-line connection is required. An in-line cable connection is typically found between the console and I/P harness.

When equipped with RPO D07, an additional USB receptacle assembly is available in the front of the console. The USB receptacles in the assembly interface with a hub device, internal to the assembly. The assembly receives fused battery voltage and ground from the harness to power the internal hub device as well as providing additional amperage to power USB devices. The internal hub device interfaces directly with the human machine interface control module via a standard USB cable.

Auxiliary Audio Input Jack

The 3.5 mm (1/8 in.) auxiliary audio input jack is located in the console. When a portable audio playback device is connected to the auxiliary jack, an internal switch opens the detection signal circuit.

The radio detects the device and AUX becomes available as an audio source. Audio signals from the device are sent to the radio from the auxiliary input jack via the left, right, and common audio signal circuits.

USB Ports

The USB port allows connectivity to the infotainment system from portable media players or a USB storage device (memory stick/ flash drive). When a device is connected to the USB port, the system detects the device and USB becomes available as an audio source. Once connected, the device can be controlled from the radio controls.

Not all portable media player devices or file types are compatible. Refer to the vehicle owner's manual for information on USB devices, control, and operation.

SD Card Reader

The infotainment uses the SD card reader as a mass storage device, similar to a USB storage device.

Refer to the owners manual for information on media types supported via the SD card reader.

Diagnostic Aids

3.5 mm (1/8 in.) Input Jack

• If the system detects the device, but the audio is not heard or is not clear, attempt to connect the device using a different cable; cables can deteriorate over time or become damaged.
• Playback of an audio device that is connected to the 3.5 mm jack can only be controlled using the controls on the device.
• The volume control on the device may need to be adjusted to ensure sufficient playback volume through the infotainment system.

USB Ports and SD Card Reader

• A low battery condition in a portable media player may not allow the device to connect to the system, or can create communication issues with the device. Verify the device battery state of charge and re-charge or replace as needed.
• Connect the device directly to the USB port if possible. Only use a cable if it is required to connect the device. The use of extension cables can cause communication issues.
• If a cable is required for connection, attempt to connect the device using a different cable; cables can deteriorate over time or become damaged.
• Attempt audio playback from multiple USB devices when diagnosing USB concerns. Device compatibility can vary based on vehicle equipment. If the infotainment system is capable of operating any USB type device, the cause of the concern is not with the vehicle system. The inoperative device (s) may be incompatible or contain no recognized media types.
• If a 'Device Not Supported' or similar type error message is displayed, this indicates the system has connected to the device but cannot communicate with it properly. This does not indicate an issue with the vehicle system. The device may be incompatible, may require a 'reset', or may require an update to its software/firmware.
• If a 'No Supported Data Found' or similar type error message is displayed, this indicates the system has connected to the device and is communicating, but cannot find any compatible files/data. This does not indicate an issue with the vehicle system. Verify the device contains compatible media/file types.
• Poor connections or damaged USB cables can cause intermittent or no operation of USB devices.

  Inspect connectors, terminals, and cables for damage and replace components as necessary.

  Ensure all USB inline connections and connections at components are fully seated and connector position retainers/locks are secure.

Reference Information

Schematic Reference

Radio/Navigation System Wiring Schematics (IOB) , Radio/Navigation System Wiring Schematics (IOR) or Radio/Navigation System Wiring Schematics (IO5/IO6) , or Radio/Navigation System Wiring Schematics (IOS/IOT).

Connector End View Reference

Component Connector End View Index

Description and Operation

Radio/Audio System Description and Operation (IO6) , Radio/Audio System Description and Operation (IOB) , or Radio/Audio System Description and Operation (IOS/IOT/IOU).

Electrical Information Reference

• Refer to Circuit Testing
• Refer to Connector Repairs
• Refer to Testing for Intermittent Conditions and Poor Connections
• Refer to Wiring Repairs

Scan Tool Reference

• Control Module References for scan tool information.

Special Tools

• EL-50334-20 Multi-Media Interface Tester (MIT)
• EL-50334-50 USB Cable and Adapter Kit
• EL-50334-14 Infotainment Test Cable

Circuit/System Verification

Auxiliary Audio Input Jack

1. Verify no DTCs are present.

• If any DTCs are present

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If no DTCs are present

2. Ignition ON, infotainment system ON.

3. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input 3.5 mm (1/8 in.) input jack and select the AUX test mode.

4. Verify that AUX becomes an available media selection to the infotainment system.

• If AUX does not become an available media selection

Refer to Circuit/System Testing - Auxiliary Audio Input Jack.

• Go to next step: If AUX becomes an available media selection

5. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.

• If audio is not heard from the test tool.

Refer to Circuit/System Testing - Auxiliary Audio Input Jack.

• Go to next step: If audio is heard from the test tool.

6. All OK

USB Ports and SD Card Reader

1. Ignition ON, infotainment system ON.

2. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input USB port and select the USB test mode.

3. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.

• If audio is not heard from the test tool

1. Insert an SD card with compatible media into the SD card slot.
2. Verify the media on the SD card can be accessed while operating the system to connect to the SD card.
   • If the SD card reader cannot be accessed, refer to Circuit/System Testing - USB Port and SD Card Reader.
   • If the SD card reader can be accessed, replace the X83 Auxiliary Audio Input.

• Go to next step: If audio is heard from the test tool

4. Insert an SD card with compatible media into the SD card slot.

5. Verify the media on the SD card can be accessed while operating the system to connect to the SD card.

• If the SD card reader media cannot be accessed

Replace the X83 Auxiliary Audio Input

• Go to next step: If the SD card reader media can be accessed

6. All OK.

Front Console USB Ports (RPO D07 - if equipped)

1. Ignition ON, infotainment system ON.

2. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X92 USB Receptacle USB port and select the USB test mode.

3. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.

• If audio is not heard from the test tool

Refer to Circuit/System Testing - Front Console USB Ports

• Go to next step: If audio is heard from the test tool

4. All OK.

Circuit/System Testing

Auxiliary Audio Input Jack

1. Ignition OFF, disconnect the X1 harness connector at the X83 Auxiliary Audio Input. Ignition ON, infotainment system ON.

2. Test for 2.5 - 3.5 V between the signal circuit terminal 5 and ground.

• If less than 2.5 V

1. Ignition OFF, disconnect the X1 harness connector at the A11 Radio.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the A11 Radio.

• If greater than 3.5 V

1. Ignition OFF, disconnect the X1 harness connector at the A11 Radio, ignition ON.
2. Test for less than 1 V between the detection circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the A11 Radio.

• Go to next step: If between 2.5 - 3.5 V

3. Test for less than 1 V between the signal circuits listed below and ground:

• Left auxiliary audio signal circuit terminal 1
• Right auxiliary audio signal circuit terminal 2
• Auxiliary audio common signal circuit terminal 3
• If 1 V or greater

1. Ignition OFF, disconnect the X1 harness connector at the A11 Radio. Ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the A11 Radio.

• Go to next step: If less than 1 V

4. Ignition OFF, disconnect the X1 harness connector at the A11 Radio.

5. Test for infinite resistance between the signal circuits listed below and ground:

• Auxiliary audio common signal circuit terminal 8
• Left auxiliary audio signal circuit terminal 9
• Right auxiliary audio signal circuit terminal 10
• If less than infinite resistance

Repair the short to ground on the circuit.

• Go to next step: If infinite resistance

6. Test for less than 5 Ω between the signal circuit terminals listed below:

• A11 Radio signal circuit terminal 9 X1 and the X83 Auxiliary Audio Input signal circuit terminal 1 X1
• A11 Radio signal circuit terminal 10 X1 and the X83 Auxiliary Audio Input signal circuit terminal 2 X1
• A11 Radio signal circuit terminal 8 X1 and the X83 Auxiliary Audio Input signal circuit terminal 3 X1
• If 5 Ω or greater

Repair the open/high resistance in the circuit.

• Go to next step: If less than 5 Ω

7. Replace the X83 Auxiliary Audio Input. Connect all harness connectors.

8. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input 3.5 mm (1/8 in.) input jack and select the AUX test mode.

9. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.

• If audio is not heard from the test tool

Replace the A11 Radio.

• Go to next step: If audio is heard from the test tool

10. All OK.

USB Port and SD Card Reader

1. Ignition OFF, disconnect the X1 harness connector at the X83 Auxiliary Audio Input.

2. Test for less than 10 Ω between the ground circuit terminal 4 and ground.

• If 10 Ω or greater

1. Ignition OFF.
2. Test for less than 2 Ω in the ground circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, repair the open/high resistance in the ground connection.

• Go to next step: If less than 10 Ω

3. Verify that a test lamp illuminates between the B+ circuit terminal 6 and ground.

• If the test lamp does not illuminate

1. Ignition OFF, remove the test lamp.
2. Test for less than 2 Ω in the B+ circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.

• Go to next step: If the test lamp illuminates

4. Verify the USB cable is properly connected at all components and in-line connections, and there is no damage to the cable or connections.

• If connection problems or cable damage is noted.

Perform the appropriate repair or replacement to correct any issues.

• Go to next step: If no connection problems or cable damage is noted.

5. Connect the X1 harness connector at the X83 Auxiliary Audio Input.

6. Disconnect the vehicle USB cable X3 harness connector at the K74 Human Machine Interface Control Module and the X83 Auxiliary Audio Input.

7. Connect the EL-50034 - 14 Infotainment Test Cable and the EL-50334 - 2 Type-A Female to Mini-B Male Cable together. Connect the assembled test cable to the K74 Human Machine Interface Control Module and the X83 Auxiliary Audio Input.

8. Ignition ON, infotainment system ON.

9. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input USB port and select the USB test mode.

10. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.

• If audio is not heard from the test tool

1. Replace the X83 Auxiliary Audio Input. Connect all harness connectors.
2. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input USB port and select the USB test mode.
3. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.
   • If audio is not heard from the test tool, replace the K74 Human Machine Interface Control Module.
   • Go to next step: If audio is heard from the test tool.
4. All OK.

• Go to next step: If audio is heard from the test tool

11. Connect the vehicle USB cable X3 harness connector at the K74 Human Machine Interface Control Module.

12. Disconnect the console to I/P USB in-line connector. Connect the assembled test cable to the I/P side of the in-line USB cable connector and the X83 Auxiliary Audio Input.

13. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 Auxiliary Audio Input USB port and select the USB test mode.

14. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.

• If audio is not heard from the test tool

Replace the I/P USB cable assembly.

• Go to next step: If audio is heard from the test tool

15. Replace the console USB cable assembly.

Front Console USB Ports

1. Ignition OFF, disconnect the X1 harness connector at the X92 USB Receptacle.

2. Test for less than 10 Ω between the ground circuit terminal 4 and ground.

• If 10 Ω or greater

1. Ignition OFF.
2. Test for less than 2 Ω in the ground circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, repair the open/high resistance in the ground connection.

• Go to next step: If less than 10 Ω

3. Verify that a test lamp illuminates between the B+ circuit terminal 6 and ground.

• If the test lamp does not illuminate

1. Ignition OFF, remove the test lamp.
2. Test for less than 2 Ω in the B+ circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.

• Go to next step: If the test lamp illuminates

4. Verify the USB cable is properly connected at all components and in-line connections, and there is no damage to the cable or connections.

• If connection problems or cable damage is noted.

Perform the appropriate repair or replacement to correct any issues.

• Go to next step: If no connection problems or cable damage is noted.

5. Connect the X1 harness connector at the X92 USB Receptacle.

6. Disconnect the vehicle USB cable X4 harness connector at the K74 Human Machine Interface Control Module and the X92 USB Receptacle.

7. Connect the EL-50034 - 14 Infotainment Test Cable and the EL-50334 - 2 Type-A Female to Mini-B Male Cable together. Connect the assembled test cable to the K74 Human Machine Interface Control Module and the X92 USB Receptacle.

8. Ignition ON, infotainment system ON.

9. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X92 USB Receptacle USB port and select the USB test mode.

10. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.

• If audio is not heard from the test tool

1. Replace the X92 USB Receptacle. Connect all harness connectors.
2. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X92 USB Receptacle USB port and select the USB test mode.
3. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the infotainment system while operating the system to play audio from the test tool.
   • If audio is not heard from the test tool, replace the K74 Human Machine Interface Control Module.
   • Go to next step: If audio is heard from the test tool.
4. All OK.

• Go to next step: If audio is heard from the test tool

11. Replace the USB cable assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Refer to Audio Disc Player and USB Receptacle Replacement
• Refer to Control Module References for radio or human machine interface control module replacement, programming, and setup.

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