Technical Tips #52
By Bob Lowe Email: firstname.lastname@example.org
Electrical connections that don't work
I have received email requests for information on various electrical components that seem to be acting in an unusual fashion and initial attempts to solve the problem have failed. As an example:
"I have a problem with my backup monitor on my 2002 Bounder. After the system has been on for about 60 minutes the monitor screen gets bright and the picture starts to fade. Sometimes the outline of the towed vehicle is still visible and then the screen will start to roll like the vertical hold is out of adjustment. If you turn the monitor off and immediately back on the picture will be normal. After anywhere from 10 to 30 minutes, the condition repeats itself. Turning the monitor off and on again corrects the problem. I contacted the manufacturer, Weldex, and they think it is the camera. They suggested that I send the camera and monitor to them for evaluation."
This problem may well be caused by a component failure, however it seems that this problem has been repeated on other Bounders of varying ages, leading me to suspect another reason.. Before sending off the component for repair, I recommend disconnecting the Camera output cable connection at the rear of the coach. Check the connection for any signs of corrosion and/or looseness. If there is high resistance between the camera and the center wire connection or the shield, the monitor could act up as described. You ask: "Why does turning the monitor off and on seem to solve the problem?" The answer is that the surge of power to the camera can temporarily override the poor connection, however as time wears on, the corrosion gets the better of it. The solution? If the connection is tight, apply a drop or two of Corrosion Block® and reconnect the wire. Even more importantly, this chemical greatly reduces the chance of a recurrence of the problem.
A similar poor signal problem often occurs on the crank-up TV antenna in the roof top connection at the TV antenna base. Many times the coach to antenna connection. (which contains a double ended female "F58" connector), corrodes and the signal does not transfer from the antenna to the booster and the TV. Typically there are times when it works and times when it does not. This connector is found under the rubber boot on the rooftop base of the TV antenna. To access it you will need to cut the caulking around the base of the boot. Lift up the boot and under it you will find the connection. If it is seriously corroded, replace it with a "F58" cable connector. Before installing the new one apply a drop or two of Corrosion Block® on each wire connection and screw them back together. Be sure to apply a small amount of self levelling lap sealer on the boot to antenna surface joint to form a water tight seal. You can use a small amount of silicone sealer, if you are careful and do not allow any sealer to contact the rubber roof,.
How does Corrosion Block® solve these problems? This chemical forms an air tight layer of protection on the wiring connection at the molecular level. Corrosion simply cannot break through the barrier and begin to deteriorate the connection. Any connection especially with dissimilar metals is a potential source of corrosion. It is for this reason that high quality Video and Audio connections made for High Definition TV and Home Theater applications are gold plated. Check out our website for more information on Corrosion Block a chemical that should be in every RVers toolkit