Hi everyone,

First post here after spending hours trawling the forum and general internet. I have done a lot of research into this and probably led myself down a few wrong paths, so I will keep this short for now.

I have a 2013 Mk3 1.6d Titanium X Focus, reverse camera is factory fitted to the Sony branded system with small screen. 

 

- Camera works 100% if you put the car in reverse (or push the park sensor button) with engine off and ignition on.

- Camera works briefly with engine running then cuts out to the "unavailable" error message on the screen 

- With engine off there is 12v at the camera and control module (in right side of boot behind trim panel)

- with engine on there is 14.3v at the camera and control module

Should the camera voltage be regulated to 12v? If so which part controls this? Is it the voltage regulator ECU under the drivers side dash area?

Should the camera be able to run at 14v?

 

I will update later with some photos.

 

Thanks in advance for any help.

Did the camera use to work fine and this fault has developed? Or, have you recently acquired the car and inherited this fault?

2 hours ago, CD82 said:

Should the camera be able to run at 14v?

Yes. Anything up to 14.9V is fine and normal.

You probably have a loose or poor video connector which is OK when there is no electrical interference with the engine off.

Check the connectors in the boot behind the panel on the RHS (I think)

2 hours ago, StephenFord said:

Did the camera use to work fine and this fault has developed? Or, have you recently acquired the car and inherited this fault?

I bought the car about 4 weeks ago and noticed the camera was playing up a couple of days after buying it, so I have inherited the issue.

45 minutes ago, unofix said:

Yes. Anything up to 14.9V is fine and normal.

You probably have a loose or poor video connector which is OK when there is no electrical interference with the engine off.

Check the connectors in the boot behind the panel on the RHS (I think)

Thank you, that is a key bit of info that I couldn't find.

 

I have checked those and did some continuity tests between there and the camera connector, but will look again.

A few edits etc to my somewhat rushed post from earlier:

 

- Camera works 100% of the time,  if you put the car in reverse (or push the park sensor button) with engine off and ignition on.

- Camera works briefly with the engine running, then after a short time (can be instant, or 5-20 seconds), cuts out to the "unavailable" error message on the screen. No warning signs like glitching video, just cuts out.

- With engine off  and ignition on, I have measured 12v at the camera and the BM5T-19H423 control module (in right side of boot behind trim panel)

- with engine running, there is 14.3v ish, measured at the camera and control module

 

- Camera model is BM5T-19G490-JB

- Can anyone tell me what voltage the white/blue LIN wire should have at the camera when activated/deactivated? I measured 8v there from memory and seemed odd to me?

 

I almost ordered a replacement camera but I don't think that will fix it at this stage. 

I will check again the video connections in the right side of the boot, and behind the bootlid trim panel and go from there I guess.

 

I have put hours into this and hate asking for help but had to give in.

Thank you for the replies so far, much appreciated. 

 

LIN bus is a single wire data communication network. Measuring voltage on the LIN bus network does not make sense. This only confirms that the LIN bus is active but says literally nothing about the actual communication, magnitude, amplitude, rate, Interference, etc.

The only way to test the LIN bus network is by performing measurements using an oscilloscope.


The LIN bus network is used for communication between the IPMB (master) and the rear view camera (slave). The IPMB uses this network to project the parking lines on top of the camera image.

1 hour ago, JW1982 said:

LIN bus is a single wire data communication network. Measuring voltage on the LIN bus network does not make sense. This only confirms that the LIN bus is active but says literally nothing about the actual communication, magnitude, amplitude, rate, Interference, etc.

The only way to test the LIN bus network is by performing measurements using an oscilloscope.


The LIN bus network is used for communication between the IPMB (master) and the rear view camera (slave). The IPMB uses this network to project the parking lines on top of the camera image.

Hi @JW1982, thank you for taking the time to read my post and the helpful reply.

That makes perfect sense, I do not currently have a scope and its been a long time since I have used one, so would probably need help to decipher the results even if I had one.

 

I spent some more time on this today, checking connections back to the camera connector by the passenger side fuse box.

I have added a ground directly from the bootlid connection point, to the camera which improved things in a way, the camera now stays on for a minute or so with the engine running. Then the error occurs again.

Have you any ideas what the issue might be? I am wondering if there is induced voltage somewhere along the loom, crosstalk interference on the LIN or MS CAN wiring, or could it be that the IPMB is failing and doesn't like running over 12v?

Thanks again.