Having had a Texecom R8 installed since 1996 the only thing that has now failed is the "5" on the Keypad, so I have replaced the old one with new 2010 version.

 

The swap out has worked fine, but the Red Zone 1 & 3 lamps are on all the time, I have check the wiring and all is OK, and I have done the the scan for Keypads "0 9" from the new keypad, all appears to be OK, but the the Red Zone 1 & 3 lamps remain on (on the keypad)

 

Date stamp on the Main box is also 1996, so is this a backwards compatabity issue with the new keypad and the old main box?

AFAIK the R8 rkps are interchangable ( they were when I last did one anyway) , are you saying the system works , but the leds remain lit , if so , rkp looks faulty.If the system wont set because 1 & 3 are lit , then you have a fault ( may need completely powering down then up again ).Have you changed the battery recently?.