Troubleshooting Video Issue

I have a video headunit plus a rear view monitor installed in my jeep, both of which worked great. I redid some of my wiring to clean it up, and after this, after driving for 20 minutes, the video signal cuts off for a second on the rear view monitor (but the monitor stays powered on). Also, sometimes the headunit itself "reboots". Something is afoot.

The things that I changed in the rewiring were:
- re-ran RCA video cables through a switch (to enable multiple cameras to connect with the monitors)
- zip-tied the video RCA cable to the bundle of stock wires running through the cab
- coiled the excess RCA video cables in a couple of spots, to deal with excess wire.
- power and ground for both the rear view monitor and cameras (but not the headunit, obviously) are now coming from a BlueSea fuse block which (via a relay) is powered on only when the car is on.   Previously it was powered with power from a fuse block (same relay trigger) but only the power wires, a separate ground was used going direct back to the battery.

Since this strange phenomenon is hitting both the headunit and the monitor, it seems it has to be tied to the RCA video cables, since that is the only common element between the two. Is there some way these cables could be picking up voltage or something since they are zip-tied to the power wires, which is causing the units to turn off?

I'm concerned that somehow there is a voltage spike or something going through the RCA's, and it's ultimately going to fry the electronics. That would suck.

My bet would be the video switch. Try connecting te rcas in-line without that switch and if you see that eliminates the problem you may need a video signal amplifier.

Thanks, I will give that a try.

In trying to troubleshoot the headunit issue, I disconnected the video cable from the headunit, but still get the "reboot". I suspect it has something to do with the fact I am drawing power from the headunit to trigger a relay. So I have:

Headunit (ACC POWER) wire -> LED-illuminated switch -> Relay
Relay allows power from the battery to get to a Blue Sea fuse panel, which I am using to power my cameras and rear view monitor.

When the LED switch is OFF, there is no reboot problem at all.
When the LED switch is ON, I have the reboot problem, but it only happens after 20 minutes or so of operation, not immediately.

This leads me to believe there is something w/ me using this wire to trip the relay that is causing the problem. But what is strange is that I used this same wire before to trip a relay, the only "new" thing is it's running through an LED switch (and the relay is different).

I'm going to try pulling power from another source to see if that makes a difference.

Figured out the "reboot" issue. It seems that the wire I was tapping into for ACC POWER isn't really able to support much of a draw at all. The LED switch was drawing around 155mA and the relay like 15mA. I simply disconnected the ground wire to the LED switch so it doesn't draw power anymore, and the problem appears to be solved.

I was surprised that 155mA was "too much" of a draw for the headunit to support, but better safe than sorry.

Now to find a 0.1A fuse to wire in-line. Any ideas there??!!

I'm surprised a LED switch draws 155mA. A bulb maybe, but even a typical LED only draws 20mA; switch LEDs are often less.

I agree, I was surprised too. The switch was supposed to draw only like 50mA or so. I don't have a super high end meter so maybe that's why the reading was so high. But whatever the incremental draw was, it was too much!

Sorry meant to say the switch was supposed to only draw 20mA.

Phew - so my assumption/guess proved correct...

So under the assumption something is wrong, and hence anything can be wrong...
IE - replace the switch.