Experiencing issues with your 2009 Mazda 6 key fob? It can be frustrating when your keyless entry suddenly stops working. Many Mazda 6 owners facing a non-responsive key fob might immediately think of expensive solutions, with dealerships often suggesting replacements like the steering column lock or keyless control module, potentially costing upwards of $1700. However, before you consider such costly repairs, the problem might be simpler and more DIY-friendly than you think.
One often-overlooked culprit for a 2009 Mazda 6 Key Fob Not Working is surprisingly the car battery. Even if your battery seems relatively new or tests as having sufficient voltage, it could still be the root of the issue. A low or failing battery can trigger diagnostic trouble codes (DTCs) within your Mazda 6’s computer system, specifically related to the immobilizer. These DTCs can prevent your car from recognizing the key fobs, effectively disabling your keyless entry and even preventing the car from starting.
The key to resolving this issue lies in clearing these DTCs. Unfortunately, a standard OBDII scanner won’t work in this situation because you likely can’t start the car or even turn the ignition to ACC mode. This is where the Mazda Integrated Diagnostic System (IDS) tool comes into play – the same tool dealerships use. The Mazda IDS allows you to “force ignition on,” even when the key fob isn’t being recognized. To do this, you’ll need the PCM/ECU part number from your Mazda 6, located behind the battery. Taking a picture can help you get this number without removing the cover.
Once you have the part number and access the Mazda IDS software, use the “force ignition on” feature and proceed to clear all DTCs. After clearing the codes, disconnect the battery completely to allow the ECU to reset itself. Wait for a short period, then reconnect the battery. In many cases, this process will resolve the key fob issue, and your 2009 Mazda 6 should once again recognize your key fobs.
It’s worth noting that even a seemingly good battery, as in the original poster’s experience where the battery was less than a year old and passed a voltage test, can still cause this problem. Therefore, before assuming more complex and expensive issues, consider the simple fix of checking your battery and clearing potential immobilizer DTCs using the Mazda IDS tool. This DIY approach could save you significant money and get your 2009 Mazda 6 key fob working again.
