Customized Linux system, wired and wireless connectivity interoperability?

The Linux system I customized runs on device A, which uses an ARM processor. Device A has an eth2 (fixed IP 192.168.5.1) and a wlan2, which is a wireless transmitter with a fixed IP 192.168.1.6. My computer can connect to device A through 192.168.1.6, but in this case, without wired connection, I can still log in to device A using 192.168.1.1; But if I am unable to log in to device A using 192.168.1.6 after connecting it with a wired connection, what is the problem?

[root@dobot ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 * 255.255.255.0 U 0 0 0 wlan2
192.168.5.0 * 255.255.255.0 U 0 0 0 eth2
192.168.100.0 * 255.255.255.0 U 0 0 0 eth1
[root@dobot ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 4E:BF:B7:B3:54:5F
inet6 addr: fe80::4cbf:b7ff:feb3:545f/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:8681 errors:2 dropped:0 overruns:0 frame:2
TX packets:8689 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:627545 (612.8 KiB) TX bytes:356046 (347.7 KiB)

eth1 Link encap:Ethernet HWaddr 00:0E:C6:87:72:01
inet addr:192.168.100.6 Bcast:192.168.100.255 Mask:255.255.255.0
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

eth2 Link encap:Ethernet HWaddr 00:0E:C6:87:72:01
inet addr:192.168.5.1 Bcast:192.168.5.255 Mask:255.255.255.0
inet6 addr: fe80::20e:c6ff:fe87:7201/64 Scope:Link
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:28924 errors:0 dropped:0 overruns:0 frame:0
TX packets:41781 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2545558 (2.4 MiB) TX bytes:5457600 (5.2 MiB)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:60760 errors:0 dropped:0 overruns:0 frame:0
TX packets:60760 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3955747 (3.7 MiB) TX bytes:3955747 (3.7 MiB)

wlan2 Link encap:Ethernet HWaddr D0:37:45:8A:68:90
inet addr:192.168.1.6 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::d237:45ff:fe8a:6890/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:157031 errors:0 dropped:589 overruns:0 frame:0
TX packets:15430 errors:0 dropped:82 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2875938 (2.7 MiB) TX bytes:4311430 (4.1 MiB)