How to deal with the illuminated OBD light in a diesel vehicle?

[KinsleyLynn]

Here are the solutions for an illuminated OBD light in a diesel vehicle: 1. Clean the three-way catalytic converter, although for some vehicles, the light may still come back on after cleaning. 2. Repair the three-way catalytic converter. If cleaning doesn't resolve the issue, check whether the catalytic converter is damaged. If it is, proceed with repairs. 3. Replace the three-way catalytic converter. If the catalytic converter is beyond repair, it's best to use an original equipment manufacturer (OEM) part, as the quality of aftermarket parts may not be guaranteed. 4. Generally, an illuminated OBD light in a diesel vehicle indicates that the vehicle's exhaust emissions exceed the standard. However, since the OBD system monitors multiple components, it can be difficult to diagnose the issue on your own. Therefore, it's advisable for the owner to visit a repair shop or a 4S store, where professional technicians can read the fault codes to identify and fix the problematic components.