I. What if the OBD system cannot detect the vehicle?
OBD system is an on-board diagnostic system. During vehicle inspection, the OBD system is usually checked, which requires using OBD diagnostic tools to read the vehicle’s OBD fault information and related data to determine if the vehicle has any fault information.
Some car owners encounter situations where the OBD system cannot detect the vehicle during inspections. This could be due to a malfunction in the OBD diagnostic tool, incompatibility with the communication protocol used by the vehicle’s ECU system, or a fault in the vehicle itself.
If the OBD system cannot detect the vehicle, try replacing it with a new diagnostic tool. If the system data is incomplete, wait for an update before proceeding with further testing. If the problem is with your vehicle, you will need to take it to a repair shop for maintenance.
II. Common OBD System Detection Problems and Solutions
Vehicles often encounter various problems during OBD system testing. Below is a summary of some common problems and solutions:
1. What to do if the vehicle has fault codes?
(1) If the lights are not working and there are fault codes, please update the software and OBD system promptly.
(2) If the fault codes persist after the update, keep the vehicle running and take it to a dealership to check if the fault codes actually exist. If they do exist, clear them.
(3) If fault codes remain after clearing them and re-diagnosing, your vehicle may indeed have a fault, and it is recommended to have it repaired as soon as possible.
(4) If the dealer does not detect any fault codes, consult them for information on upgrading to the latest ECU system.
2. What if OBD communication fails or connection fails?
(1) Check if there is dust on the vehicle’s OBD interface. Clean it thoroughly before connecting.
(2) For earlier, lower-spec models, the onboard ECU system may not include emissions monitoring functionality. Please visit your dealership to upgrade this system.
(3) If the OBD connection fails, please upgrade the OBD version at the inspection station to the latest version and try again; or check with the dealer to see if the vehicle’s OBD is in stock.
3. What if more than two items in the ready status are incomplete?
(1) For vehicles in good condition that have undergone regular maintenance, please drive them fully until all sensors reach their optimal state before re-inspecting them.
(2) For vehicles that have not been regularly maintained and are in poor condition, it is recommended to clean the entire assembly.
(3) If neither method 1 nor method 2 can resolve this issue, the ECU will need to be upgraded to the latest version at the dealership.
4. Why can’t some vehicles have their OBD information read at vehicle inspection stations, while the OBD information for all vehicles can be read at dealerships?
Dealers use the original equipment manufacturer’s (OEM) protocol, allowing them to read the information for their own vehicle models. This enables dealerships to quickly diagnose vehicle conditions and perform repairs using OBD data.