Troubleshooting

MULTI-Module LEDs
LEDs are present on most external MULTI-Modules and can be used to check the status of the module.
The basic functions of the LEDs are:
Green LED - indicates that the MULTI-Module is receiving power
Red LED - indicates the status of the MULTI-Module
On TMX5 modules the red LED patterns are reversed.  (Also note that TMX5 modules are not officially supported.)
Red LED State
Pattern
Meaning
Off
Off
The module is not functioning.
Flashing
On 0.05s; Off 1s
The selected protocol is not available on the module.
Inverted Flashing
On 1s; Off 0.1s
Waiting for bind to be initiated.
Fast Blink
On 0.1s; Off 0.1s
Binding in progress.
Slow Blink
On 0.5s; Off 0.5s
Module is in Serial Mode but there is no signal from the radio.
Very Slow Blink
On 1s; Off 1s
Module is in PPM Mode but there is no signal from the radio.
Fast Double Blink
On 0.1s; Off 0.1s;
On 0.1s; Off 0.5s
Serial debugging is waiting for a serial connection.
On
On
The module is operating (transmitting).
SOS
Three short; three long; three short
The firmware has detected that it is running on an MCU with less than 128KB of flash memory.
Module Status
OpenTX and EdgeTX will display the state of the MULTI-Module in the Module Status line of the RF module section on the Model Setup page.
Normal Operation
In normal operation the Module Status will display the MULTI-Module firmware version and the Expected Channel Order.
Module Status with Firmware Version and Channel Order
If an auto-binding protocol is selected, and binding has not yet been initiated, the Module Status will display "Bind to load protocol".
Module Status waiting for Bind
When the module is binding, the Module Status will display the firmware version followed by "Binding".
Module Status Binding
No MULTI Telemetry
If the Module Status displays "No MULTI_TELEMETRY" or "No telemetry" there is a problem with the MULTI-Module
Module Status No MULTI Telemetry
In this situation, one of the following may be the cause:
The selected module is not installed - External is selected when Internal should be, or vice-versa
The wrong firmware is installed on the module - the wrong radio firmware, or telemetry inversion setting was used
The module is defective
A somewhat common fault is bad solder joints on the 5-pin module bay connector
Getting Help
There are two ways to get help:
RC Groups Forum - for general 'how-to' questions or advice from other users
GitHub Issues - for reporting bugs or serious issues
RC Groups is usually the best place to start as the forum is very active, with many experienced users who can provide help and answer questions.
To make it easier to provide help, please include the following information:
MULTI-Module type and the firmware version
Radio type, firmware, and firmware version
Using PPM or Serial
Description of what the LED on the MULTI-Module and the receiver/model are doing
Explanation of the behaviour and reproduction steps

Last modified 4mo ago

Red LED State	Pattern	Meaning
Off	Off	The module is not functioning.
Flashing	On 0.05s; Off 1s	The selected protocol is not available on the module.
Inverted Flashing	On 1s; Off 0.1s	Waiting for bind to be initiated.
Fast Blink	On 0.1s; Off 0.1s	Binding in progress.
Slow Blink	On 0.5s; Off 0.5s	Module is in Serial Mode but there is no signal from the radio.
Very Slow Blink	On 1s; Off 1s	Module is in PPM Mode but there is no signal from the radio.
Fast Double Blink	On 0.1s; Off 0.1s; On 0.1s; Off 0.5s	Serial debugging is waiting for a serial connection.
On	On	The module is operating (transmitting).
SOS	Three short; three long; three short	The firmware has detected that it is running on an MCU with less than 128KB of flash memory.