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 Component Replacement/Key Addition And Clearing[Advanced Keyless System]: Foreword
2008 Mazda CX-7 Touring, 2.3 3, AWDSECTION Foreword
- When performing the following procedures, the immobilizer resetting procedure using the M-MDS must also always be performed: "Keyless control module replacement", "PCM replacement", "Steering lock unit replacement", "Keyless control module and PCM joint replacement", "Keyless control module, PCM, and steering lock unit joint replacement", and "Key ID number clearing". The engine will not start unless all work is performed using the M-MDS.
- A card key that can start the engine is necessary for the key programming. If there is no card key that can start the engine, perform the key programming after the card key programming. (See CARD KEY ID CODE REGISTRATION[ADVANCED KEYLESS SYSTEM] .)
- There are two ways to add supplemental key: Using the M-MDS or using two keys that can start the engine to program.
- When replacing any of the immobilizer system component parts, adding/clearing keys, or performing other functions, refer to the following table and perform the applicable procedure (NO. 1 to 5).
- Verify that the room fuse is equipped.
IMMOBILIZER SYSTEM REFERENCE
| Ref. No. | Condition | Items necessary for procedure (prepare before starting procedure) | Cautionary notes |
|---|---|---|---|
| 1 | Since two or more keys that can start the engine are necessary, make a spare key. Or program an additional key. |
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| 2 | If there is only one key that can start the engine, make a spare key. If there is no key, program an additional key. |
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| 3 | Replacing the PCM only. |
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| 4 | Changing the additional key programming procedure. (Method for programming other keys using two keys that can start the engine is disabled.) |
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| 4 | Changing the additional key programming procedure. Allows programming using two keys that can start the engine. |
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| 5 | Clearing the programmed key ID number. |
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| 5 | Replacing all the keys. (Steering lock unit is not replaced) |
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| 5 | Replacing the steering lock unit. |
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| 5 | Replacing the keyless control module. |
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| - | Replacing the coil antenna. |
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CAUTION:
- The following conditions may cause poor signal communication between the key and vehicle, resulting in the engine not starting or a key registration error. Do not perform any work under the following conditions:
- Placing the following items close to the key grip or contacting it.
- Spare keys
- Keys for other vehicles equipped with an immobilizer system
- Any metallic object
- Any electronic device, or any credit or other card with magnetic strips
- Placing the following items close to the key grip or contacting it.
- Do not place the following devices in the vehicle while programming, otherwise programming cannot be performed:
- M-MDS
- Personal computer
- Devices that can send/receive the radio waves
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:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.