B124C

DTC B124C

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B124C 0B
- USB 2 Circuit Current Above Threshold

DTC B124C 04
- USB 2 Circuit HUB Open Circuit

DTC B124C 11
- USB 2 Circuit HUB Above Maximum Threshold

Circuit/System Description

The infotainment system has a USB port and SD card reader slot located in the center console. The USB port and the card reader slot interface with a hub device, internal to the auxiliary jack, USB, and memory card receptacle assembly. The auxiliary jack, USB, and memory card receptacle 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 USB port and at the human machine interface control module and at the auxiliary jack, USB, and memory card receptacle. 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.

USB Port

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 switches to USB as the 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 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.

Conditions for Running the DTC

* Ignition is ON or in the ACC position

* The system voltage is 9-16 V

* The infotainment system is ON

* The test is run once per second when the infotainment system is operating

Conditions for Setting the DTC

B124C 0B

The human machine interface control module detects an excessive current condition on the USB 5 V circuit.

B124C 04

The human machine interface control module does not detect the vehicle hub device.

B124C 11

The human machine interface control module detects an additional hub device attached to the vehicle USB port.

Action Taken When the DTC Sets

The USB port and SD card reader are inoperative while the DTC is current.

Conditions for Clearing the DTC

* The condition for setting the DTC is no longer present.

* A history DTC will clear once 50 consecutive malfunction-free ignition cycles have occurred.

Diagnostic Aids

* This DTC may be set due to the connection of an incompatible or faulty USB device.

* The Human Machine Interface Control Module has two available USB connections. The Human Machine Interface Control Module calibrations determine what is expected to be connected to each of these connection: either a USB port or a USB/SD Card reader HUB. USB 1 and USB 2 refers to the connector at the module that the port or hub is connected to.

Reference Information

Schematic Reference

Radio/Navigation System Schematics Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views Fuel Pump and Level Sensor Assembly

Description and Operation

Radio/Audio System Description and Operation Radio/Audio System

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Verify DTC B124C is not set. Since occurrences of this DTC can be caused by an incompatible or faulty USB device, review with the customer the conditions under which their concern occurred.

• If DTC B124C is set.
Refer to Circuit/System testing.

• If DTC B124C is not set.

2. Ignition ON, infotainment system ON.

3. Verify that USB becomes an available media selection with a portable audio playback device connected to the USB port.

• If USB does not become an available media selection
Refer to Circuit/System Testing.

• If USB becomes an available media selection

4. Verify the audio from the device is heard through the infotainment system while operating the system to play audio from the device.

• If audio is not heard from the device

1. Connect a different device to the USB port.

2. Verify the audio from the device is heard through the infotainment system while operating the system to play audio from the device.

• If audio cannot be heard from any device connected to the USB port, refer to Circuit/System Testing.

• If audio can be heard from device.

3. The malfunction was related to the external device connected to the input.

• If audio is heard from the device

5. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the X1 harness connector at the X83 auxiliary audio input.

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

• If 10 ohms or greater

1. Ignition OFF.

2. Test for less than 2 ohms in the ground circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, repair the open/high resistance in the ground connection.

• If less than 10 ohms

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.

2. Test for less than 2 ohms in the B+ circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If the test lamp illuminates

4. Ignition OFF, connect the X1 harness connector at the X83 auxiliary audio input.

Note: USB cables and adapters for the following tests are found in the EL-50334-50 - USB cable and adapter kit.

5. Disconnect the USB cable connection at the X83 auxiliary audio input and at the I/P to floor console inline USB cable connector

6. Connect the EL-50334-2 Type A female to Mini B male USB Cable to the X83 auxiliary audio input and the I/P side of the I/P to floor console inline USB cable connector.

7. Ignition ON, infotainment system ON, connect a USB device to the X83 auxiliary audio input.

8. Verify that USB is not an available media selection.

• If USB is an available media selection
Replace the console side USB cable assembly.

• If USB is not an available media selection.

9. Ignition OFF, connect the vehicle USB cable to the X83 auxiliary audio input.

10. Disconnect the USB cable at the K74 human machine interface control module.

11. Connect the EL-50334-1 Type A male to Mini A male USB Cable to the K74 human machine interface control module and the console side of the I/P to floor console inline USB cable connector.

12. Ignition ON, infotainment system ON, connect a USB device to the X83 auxiliary audio input.

13. Verify that USB is an available media selection.

• If USB is not an available media selection.

1. Replace the X83 auxiliary audio input.

2. Connect all harness connectors.

3. Ignition ON, infotainment system ON, connect a USB device to the X83 auxiliary audio input.

4. Verify USB is an available media selection.

• If USB is not an available media selection, replace the K74 human machine interface control module.

• If USB is an available media selection.

14. Replace the I/P side USB cable assembly.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Audio Disc Player, USB, Auxiliary In, and Memory Card Receptacle Replacement Service and Repair

* Control Module References Control Module References for human machine interface control module replacement, programming, and setup.