5000hx which currently has 8520/8560 digital handsets but won't take 8568s?

[brandscape]

We have a 5000hx system which we currently use 8520 and 8560 digital handsets. Have decided to get some cheap reconditioned handsets, saw there was an 8568 handset that looked like it would work yet it doesn't. No display, no nothing, have tried with existing cords and plugging directly into the patch panel, the phones have  space for 24v power not sure if it that is needed? Anyone any idea? We have version 6 of software so don't think that is the issue?

[acejavelin]

The older 8520/8560 phones use pins 2&5 of a six pin jack (2nd line, yellow/black of 6-pin jack, or w/gr of a 568B jack), but the 8568 phones use pins 3&4 of a six pin jack (1st line, red/green, or w/bl of a 568B jack). In order to use these phones you will need to get your jacks rewired to use the appropriate pins in the jack.

[dwayneg]

Or back on your 66 blocks move the cross-connect from orange pair to blue pair.

[brandscape]

Cheers both, thought it would be something easy. They work fine now!