THE CHECK ENGINE LIGHT
Every new car now comes with OBD-II – On Board Diagnostics 2. This is a fault-registering system connected to sensors all over the car, engine, fuel and emissions system. When the check engine light comes on, it can mean many things. There are something like 4,000 unique OBD2 codes that can be stored. Handheld OBD2 diagnostic tools can be plugged in to the OBD2 port which is normally under the dash on the driver’s side. These tools can read out the fault code and/or reset the system to contain no codes. Codes are split into two categories – historical/inactive, and active. The historical codes are lists of things that have been detected in the past but are no longer an issue, whilst the active codes are things that are a problem right now. Codes are subdivided into B-codes (body), C-codes (chassis) and the biggest list of all – P-codes (powertrain).