How to Interpret/Read the LEDs for USB Cable Testers

NOTE This is a work in progress. Please leave comments or better, pull requests, with updates. Please verify with actual cables.

This "application" is hosted on GitHub pages: Interpreting the LEDs on a USB Cable Tester.

Description

For the initial work, I am using the Treedix USB Cable Tester (affiliate link). The Treedix USB Cable Tester (affiliate link) is an inexpensive, but highly functional USB Cable Tester. You can use it to identify and test many different types of USB cables, including unusual ones.

Others should use this same pattern, but there could be additional things other cable testers are testing for. Feel free to send me one, and I'll add it here.

References

• USB hardware - Wikipedia
• USBefuddled: Untangling the Rat's Nest of USB-C Standards and Cables

USB Cable Types

Wikipedia's article on USB Hardware shows the standards for USB Cables - that is, what plugs can be on each end.

The Treedix USB Cable tester can test the following plugs:

• Apple Lightning
• USB 2.0 A
• USB 2.0 Mini-B
• USB 2.0 Micro-B
• USB 3.0 A
• USB 3.0 Micro-B
• USB 3.0 B
• USB 3.0 C (Male and Female)

You can use this diagram to understand what each plug looks like and the common arrangements.

Interpreting the LEDs

The Treedix manual includes some examples of common USB functions, but not all.

On the bottom left is a set of two LEDs, ID and Shield.

ID		Indicates the presence of an ID chip
Shield		Indicates a shield

Charging Only

• Some USB 2.0 A, Mini-B, Micro-B

These are often inexpensive cables included with electronic devices by the manufacturer for charging purposes only.

Pinrow B	Name	LED		Pinrow A	Name	LED
B1	GND			A12	GND
B2	TX2+			A11	RX2+
B3	TX2-			A10	RX2-
B4	VBUS			A9	VBUS
B5	CC2			A8	SBU1
B6	D+			A7	D-
B7	D-			A6	D+
B8	SBU2			A5	CC1
B9	VBUS			A4	VBUS
B10	RX-			A3	TX1-
B11	RX+			A2	TX1+
B12	GND			A1	GND

Verified with cable

Charging & Data

• Many USB 2.0 A, Mini-B, Micro-B

This is the expected response of a fully functional USB 2.0 cable

• Some USB 3.0 A

Pinrow B	Name	LED		Pinrow A	Name	LED
B1	GND			A12	GND
B2	TX2+			A11	RX2+
B3	TX2-			A10	RX2-
B4	VBUS			A9	VBUS
B5	CC2			A8	SBU1
B6	D+			A7	D-
B7	D-			A6	D+
B8	SBU2			A5	CC1
B9	VBUS			A4	VBUS
B10	RX-			A3	TX1-
B11	RX+			A2	TX1+
B12	GND			A1	GND

Not Verified with cable

Charging & Data

• Many USB 2.0 A, Mini-B, Micro-B

This is the expected response of a fully functional USB 2.0 cable

• Some USB 3.0 A

Pinrow B	Name	LED		Pinrow A	Name	LED
B1	GND			A12	GND
B2	TX2+			A11	RX2+
B3	TX2-			A10	RX2-
B4	VBUS			A9	VBUS
B5	CC2			A8	SBU1
B6	D+			A7	D-
B7	D-			A6	D+
B8	SBU2			A5	CC1
B9	VBUS			A4	VBUS
B10	RX-			A3	TX1-
B11	RX+			A2	TX1+
B12	GND			A1	GND

Verified with cable

Charging Only - Converters

• Some USB 2.0 A to USB-C

Provides power to both ends of the cable.

Pinrow B	Name	LED		Pinrow A	Name	LED
B1	GND			A12	GND
B2	TX2+			A11	RX2+
B3	TX2-			A10	RX2-
B4	VBUS			A9	VBUS
B5	CC2			A8	SBU1
B6	D+			A7	D-
B7	D-			A6	D+
B8	SBU2			A5	CC1
B9	VBUS			A4	VBUS
B10	RX-			A3	TX1-
B11	RX+			A2	TX1+
B12	GND			A1	GND

Verified with cable

Charging and Data - Converters 1

• Some USB 2.0 A to USB-C

Provides power to both ends of the cable and is capable of data.

Pinrow B	Name	LED		Pinrow A	Name	LED
B1	GND			A12	GND
B2	TX2+			A11	RX2+
B3	TX2-			A10	RX2-
B4	VBUS			A9	VBUS
B5	CC2			A8	SBU1
B6	D+			A7	D-
B7	D-			A6	D+
B8	SBU2			A5	CC1
B9	VBUS			A4	VBUS
B10	RX-			A3	TX1-
B11	RX+			A2	TX1+
B12	GND			A1	GND

Verified with cable

Charging and Data - Converters 2

• Some USB 2.0 A to USB-C

Provides power to both ends of the cable and is capable of data.

Pinrow B	Name	LED		Pinrow A	Name	LED
B1	GND			A12	GND
B2	TX2+			A11	RX2+
B3	TX2-			A10	RX2-
B4	VBUS			A9	VBUS
B5	CC2			A8	SBU1
B6	D+			A7	D-
B7	D-			A6	D+
B8	SBU2			A5	CC1
B9	VBUS			A4	VBUS
B10	RX-			A3	TX1-
B11	RX+			A2	TX1+
B12	GND			A1	GND

Verified with cable

Charging & High Speed Data

• Most USB 3.0 A, Micro-B
• Many USB-C 3.0

Pinrow B	Name	LED		Pinrow A	Name	LED
B1	GND			A12	GND
B2	TX2+			A11	RX2+
B3	TX2-			A10	RX2-
B4	VBUS			A9	VBUS
B5	CC2			A8	SBU1
B6	D+			A7	D-
B7	D-			A6	D+
B8	SBU2			A5	CC1
B9	VBUS			A4	VBUS
B10	RX-			A3	TX1-
B11	RX+			A2	TX1+
B12	GND			A1	GND

Not Verified with cable

Charging, High Speed Data, Audio and Voice

• Many USB-C 3.0

Pinrow B	Name	LED		Pinrow A	Name	LED
B1	GND			A12	GND
B2	TX2+			A11	RX2+
B3	TX2-			A10	RX2-
B4	VBUS			A9	VBUS
B5	CC2			A8	SBU1
B6	D+			A7	D-
B7	D-			A6	D+
B8	SBU2			A5	CC1
B9	VBUS			A4	VBUS
B10	RX-			A3	TX1-
B11	RX+			A2	TX1+
B12	GND			A1	GND

Not Verified with cable

Apple Lightning

Pinrow B	Name	LED		Pinrow A	Name	LED
B1	GND			A12	GND
B2	TX2+			A11	RX2+
B3	TX2-			A10	RX2-
B4	VBUS			A9	VBUS
B5	CC2			A8	SBU1
B6	D+			A7	D-
B7	D-			A6	D+
B8	SBU2			A5	CC1
B9	VBUS			A4	VBUS
B10	RX-			A3	TX1-
B11	RX+			A2	TX1+
B12	GND			A1	GND

Verified with cable