Use this article if…
- Use this article only on MK4 when you select reverse and it clearly opens the camera view (the layout or source changes) and the video area is black, blank, or shows “no signal”, even if you still get a picture from another camera input.
- Don't use this article if reverse never takes you off radio, maps or CarPlay/Android Auto → that's a trigger / input assignment problem: No reverse camera showing when in reverse.
- Don't start with this article if you can see a live picture that's rolling, wrong colours, or scrambled (not a blank feed). Start with Camera troubleshooting overview for AHD/CVBS and cabling context.
- Other headunits → Black / wrong picture.
Quick answer
If you select reverse and the screen opens but stays black, that's very often an AHD and CVBS mismatch. Toggle the camera format in MK4 settings, reboot once, then test again in reverse.
Problem
- Your reverse view opens but the image stays black or shows no signal.
Symptoms
- When you select reverse the camera page opens, but the image area stays black or shows “no signal.”
- You may still get a picture from another source, like a front camera on a different input.
Cause
- AHD and CVBS mismatch. Your headunit is decoding the wrong standard.
- Your camera or the cable on that coax run has a fault.
- Very low light on entry-level sensors. That's rare, and you're usually chasing a format issue first.
Fix Step-by-step
- In MK4 camera / video settings, set the format to match your camera: CVBS N for a factory or standard analogue camera, AHD 720P25 for a PVS AHD camera. Restart the unit after you change it. Common mistake: you tap auto once without a deliberate AHD ↔ CVBS toggle. After each change, key fully off and on once, then test in reverse.
- Still black after both formats: with reverse engaged, gently flex the coax barrel. If you see the picture flash, re-seat or replace the connector or adapter. If flexing does nothing, swap the camera to another allowed RCA input with a helper in reverse. If you get video on a different port, the original input path or extension is suspect.
- Meter the reverse camera supply and trigger against your sheet. Some cameras stay black if +12 V on the video line is weak, or if the trigger never rises. Common mistake: you read black as a format issue when the camera never fully powers. Use Camera wiring for routing checks.
- If you had a picture from this camera on the factory screen, compare the adapter. A wrong video pin or a missing feed can look like no signal. If the reverse page never opens at all, stop here and use No reverse display. Overview → Camera troubleshooting.
Notes
- No camera page in reverse, stays on radio: No reverse display
- Wiring: Wire cameras to the MK4
- Overview: Camera troubleshooting
- Format primer: AHD vs CVBS
Still stuck? Send us these photos
- Vehicle: model, series and year.
- Screenshot: your MK4 camera / video format page showing whether it's set to AHD, CVBS or NTSC after your last toggle and key cycle.
- Photos: the camera label or part number, and the RCA/coax at the headunit and at the camera tail with the connectors fully seated.
- Short clip: reverse engaged after a key cycle. Hold on the black or “no signal” view for a few seconds.
- State: do you get a picture from another camera input on the same headunit, or is every video input dead?