Cannot setup wireless printing on Dell c1660w Color Laser Printer

I don't have the printer, but what I'd try is the
Manual SSID setup (Infrastructure) as described in the manual.
Make sure also that the MAC filter on the router (if enabled) does allow the printer to connect.

NOTE: A Password is required to enter Admin Menu when Panel Lock Set is set to Enable. In this case, enter
the password you specified, and press the (Set) button.
1 Press the (Menu) button.
2 Press the button until Admin Menu appears, and then press the (Set) button.
3 Press the button until Network appears, and then press the (Set) button.
4 Press the button until Wireless Setup appears, and then press the (Set) button.
5 Press the button until Manual Setup appears, and then press the (Set) button.
6 Enter the SSID, and then press the (Set) button.
7 Select the network mode from Infrastructure and Ad-hoc depending on your environment, and then press
the (Set) button.
If you select Infrastructure, proceed to step 8.
If you select Ad-hoc, proceed to step 9.
8 Select the encryption type from No Security, Mixed mode PSK, WEP, WPA-PSK-TKIP, or WPA2-PSKAES.
If you do not set security for your wireless network:
• Press the button until No Security appears, and then press the (Set) button.
To use Mixed mode PSK, WPA-PSK-TKIP, or WPA2-PSK-AES encryption:
a Press the button until Mixed mode PSK, WPA-PSK-TKIP, or WPA2-PSK-AES appears, and then
press the (Set) button.
b Enter the passphrase, and then press the (Set) button.
NOTE: A passphrase is an encryption key for WPA and WPA2 encryption which consists of 8 to 63 alphanumeric
characters. It may be described as a key on some access points or routers. For details, refer to the manual supplied with
the access point or router.
To use WEP encryption:
a Press the button until WEP appears, and then press the (Set) button.
b Enter the WEP key, and then press the (Set) button.
c Press the button to highlight the desired transmit key from Auto or WEP Key 1 to WEP Key 4, and
then press the (Set) button.
Ensure that Restart Printer to apply settings appears.
Turn off the printer, and turn it on again to apply the settings.
Wireless LAN connection setting is complete.