How to retrofit a rear view / reverse camera to a Ford Focus MK4
Old how-to with just pictures (I will leave it online anyway)
Required camera: Link
After installation, activate the camera using FORScan: Rear Vehicle Camera – enable
Step 1: Unscrew the center console and dashboard
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Step 2: Locate the APIM module
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Step 3: remove the connector
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Step 4: attach camera pins to connector
Pin 14 Video +
Pin 15 Video –
Pin 33 Grund
Step 5: move the camera to the rear
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Step 6: functional tests
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Many thanks to Mathias alias hucky0611 for the information and the pictures provided