Slide out issues

Hello , First time here. My son in law just purchased his first rv. 2002 Fleetwood Wilderness 31g. From the first owner, he rarely used it. We could not get the slide out to work. After much trouble shooting, we found the relay board to be bad. Ordered a new one, installed it. Pressed the slide button to extend the slide out and worked great. Pressed the button to retract and nothing. Tested the realy board and everything is good. So we thought maybe bad switch. Tested 12V wire on switch and had 13.6 volts. placed a jumper wire on the 12V feed and then the retract wire, and the slide went out, placed the 12V feed on the extend wire and nothing. Hooked the 12V feed back into the switch and the extend wire back onto the switch and nothing, hooked the retract wire back on the switch and the extend would then work, but not the retract. Any ideas folks?