Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Immobilizer System (Keyless Entry System)
2012 Mazda 6 V6-3.7LSECTION Immobilizer System (Keyless Entry System)
DTC INSPECTION [IMMOBILIZER SYSTEM (KEYLESS ENTRY SYSTEM)]
Security Light
1. Switch the ignition to ON.
2. Verify the security light status.
- If a malfunction is detected, the DTC pattern begins flashing after the security light flashes or illuminates for approx. 1 min according to the DTC. However, because there are DTCs which cannot be confirmed using the security light, verify the DTCs that were detected using the M-MDS prior to beginning the servicing.
- DTC 16 or below: Flashes for approx. 1 min and the DTC flash pattern repeats 10 times.
- DTC 21 or higher: Illuminates for approx. 1 min and the DTC flash pattern repeats 10 times.
- If more than one DTC is detected, only the DTC with the lowest number is displayed.
- If there is no malfunction, the security light illuminates for approx. 3 s, and then turns off.
3. If there is a malfunction, verify the DTCs using the M-MDS. When several DTCs are detected, repair the malfunctioning location based on the DTC displayed by the security light.
NOTE:
- Because of the possibility that one malfunction cause could result in several DTCs being detected, erase the DTCs after the repair is completed, and then re-inspect the DTCs.
4. After completion of repairs, clear all DTCs stored in the Instrument cluster and PCM.
M-MDS
1. Connect the M-MDS (IDS) to the DLC-2.
2. After the vehicle is identified, select the following items from the initialization screen of the IDS.
a. Select "Self Test".
b. Select "Modules".
c. Select "IC".
3. Verify the DTC according to the directions on the screen.
- If any DTCs are displayed, perform troubleshooting according to the corresponding DTC inspection. When several DTCs are detected, repair the malfunctioning location based on the DTC displayed by the security light.
Immobilizer System (Keyless Entry System) - DTC Table
NOTE:
- Because of the possibility that one malfunction cause could result in several DTCs being detected, erase the DTCs after the repair is completed, and then check for DTCs again.
4. After completion of repairs, clear all DTCs stored in the Instrument cluster and PCM.
Immobilizer System (Keyless Entry System)
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.