MX7 system is restarting automatically

Problem

The MX7 system restarts automatically after approximately 50-55 seconds, or after a mission is started. When checking the core logs, you will find logs that end abruptly without the expected "Api;Shutdown completed;" entry at the end.

Solution

In the majority of cases, the described problem can be overcome by simply turning on the car's headlight or the air conditioning. This will trigger the alternator, ensuring that required power to the MX7 is provided. It is crucial that the alternator starts to run before turning on the MX7, and it has to last at least the first minute of the system startup until the system is fully booted and until the mission starts. After that, extra loads such as headlight or AC can be turned off again.

The MX7 can draw up to 10 A @ 12 V from the vehicle battery during the system startup. Depending on the make and model of the car, the vehicle battery management system can behave differently, which affects the re-charging of the battery, and, consequently the amount of current that can be provided at a specific time. Therefore, in some instances, it is possible that the vehicle battery does not supply sufficient power for the system to startup. In this case, the MX7 would shut down and attempt to reboot.

The MX7 startup sequence is as follows:

  1. System Status LED is solid ON (system is booting).
  2. System Status LED start blinking (the system is booted).
  3. System Status LED stays blinking for more than 55 seconds (system receives enough power and is ready to operate).

During step number three, two scenarios have been identified:

  • Scenario 1: System Status LED switches from blinking to solid ON or solid OFF (the system is restarting) approx. 50-55 seconds after pressing the Power button.
  • Scenario 2: System Status LED switches from blinking to solid ON or solid OFF (system is restarting) after starting a mission in TMI.

In both scenarios, the system is restarting because the car's battery or the car battery management system does not supply sufficient power. As soon as a power shortage is identified, the system must be manually shut down by pressing the Power button.

In case of a system reboot, the WiFi will drop temporarily and the TMI interface will hang. Note that the symptom is the same as for a generic WiFi issue. This is not to be confused and monitoring the System Status LED on the Power Box will help to rule out the possibility of a WiFi connection problem.

Related Products

MX7

Support Reference

00678561