Question edited for clarity.
Question moved to RVs.
Normally they are wired so they only work when you are in reverse.
Check the wiring for bad connections. I am guessing the wiring in under the RV zip tied or glued to the chassis with adhesive putty.
The RV Forum seems to have the answer
https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/25043162/print/true.cfm
Posted By: camers on 05/07/11 09:17pm
Several of us Weldex owners had the same problem, changing monitors, rear cameras, and ground wires did not fix the problem. Finally, someone said to cut off the camera connectors at the rear camera and solder the wires together. It's been almost two years now and the camera has worked flawlessly. Al 2007 Travel Supreme Alante
Posted By: J-Rooster on 05/07/11 11:05pm
larry cad wrote:
Contact Tim at:
http://www.rvcams.com/Default.htm
Nobody in the business any better.
I agree totally with this post! Send Tim an e-mail and he is right on it!
Posted By: Buck62 on 05/08/11 08:26am
The Weldex B/W model WDRV-3007M has been obsoleted. When mine went out I called Weldex support and was told that the circuit board solders just did not stand up to the jarring of road travel. He recommended that I first replace the connectors at each end after cutting off approximately 8-12" of the cable since sometimes there is a short in the cables due to flexing. If this did not work I should upgrade to their color LCD replacement system. I called Tim at RVCams.com and he recommended the Weldex color LCD replacement since it used the same wiring and was a exact size replacement with the special mounting bracket. I have had mine for several years now and it has functioned perfectly.
https://www.google.com/search?q=wdrv-3007m
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