Hello, I am a brand new member of the BAC Forum. The latest project that I have completed on my coach was replacing the keyless entry key pad. I have done a search for posts on this subject and found 2 pages of posts. I read quit a few of them but I did not see any that used the same solution as I did. So I thought I would post my solution. To make a long story short my keyless Essex 1603 key pad stopped working correctly and needed to be replaced. I had the Essex 1603 keyless system. since the 1603 system is no longer available and has been replaced with the Essex KE1704 . I compared the wiring diagrams of both the 1603 and the 1704 and they are identical. so I ordered 1704 key pad. Besides having to splice 12 small wires the only other modification I had to make was the location hole for the key pad needed to be a little bit larger. now everything works as it is supposed to .