Reprogramming system and reprogramming tool

A reprogramming system comprising:

• modules configured to be provided in a vehicle, the modules comprising a target module for which reprogramming is to be performed and a non-target module coupled to the target module so as to communicate with the target module;
• and
• a reprogramming tool coupled to the modules so as to communicate with the modules, wherein the reprogramming tool comprises
• one or more processors, and
• one or more memories coupled to the one or more processors, and
• wherein the one or more processors are configured to perform
• a transmission process to transmit data for the reprogramming to the target module,
• a retry process to perform the transmission process again in a case where a predetermined condition is met, and
• a message transmission process to transmit, before the retry process, a message to at least the non-target module among the modules, the message indicating that communication between the reprogramming tool and the target module is being continued.