1# NFC Error Codes
2
3> **NOTE**
4>
5> This topic describes only module-specific error codes. For details about universal error codes, see [Universal Error Codes](../errorcode-universal.md).
6
7## 3100101
8
9**Error Message**
10
11NFC state is abnormal in service.
12
13**Description**
14
15The NFC service fails to enable or disable NFC.
16
17**Possible Causes**
18
191. Communication with the NFC service failed.
202. The NFC chip communication is abnormal.
21
22**Solution**
23
241. Enable or disable NFC again.
252. Enable or disable NFC again or restart the device, and try again.
26
27## 3100201
28
29**Error Message**
30
31Tag running state is abnormal in service.
32
33**Description**
34
35An error occurs when the NFC service executes the tag service logic.
36
37**Possible Causes**
381. The tag parameters do not match the API to invoke.
392. The NFC is disabled.
403. The tag is disconnected before the tag operation.
414. The tag chip returns an error status or response timeout.
425. Binding with the NFC service has not been established.
43
44**Solution**
451. Check whether the NFC parameters match the API to call.
462. Instruct the user to enable NFC if it is disabled.
473. Connect to the tag and then perform the read and write operations.
484. Touch and read the card again.
495. Exit the app and read the card again.
50
51## 3100202
52
53**Error Message**
54
55The element state is invalid.
56
57**Description**
58
59When the API is called, the application of the card read page is not running in the foreground.
60
61**Possible Causes**
621. The card read page is not in the foreground.
63
64**Solution**
651. The API can be called only by the page in the foreground.
66
67## 3100203
68
69**Error Message**
70
71The off() can be called only when the on() has been called.
72
73**Description**
74
75The off() API can be called only after on() is called.
76
77**Possible Causes**
781. The foreground page of the application calls **off()** without invoking **on()**.
79
80**Solution**
811. Call **on()** first, and call **off()** before the page exits.
82
83## 3100204
84
85**Error Message**
86
87Tag I/O operation failed.
88
89**Description**
90
91The NFC tag I/O operation fails.
92
93**Possible Causes**
941. The NFC tag does not support the read/write operation.
95
96**Solution**
971. Implement error handling and display error messages based on service scenarios.
98
99## 3100301
100
101**Error Message**
102
103Card emulation running state is abnormal in service.
104
105**Description**
106
107An error occurs when the NFC service executes the card emulation service logic.
108
109**Possible Causes**
1101. NFC is disabled during card emulation.
1112. The NFC chip returns an error status or response timeout.
112
113**Solution**
1141. Instruct the user to enable NFC if it is disabled.
1152. Instruct the user to disable and enable NFC to initialize the hardware again.
116
117## 3200101
118
119**Error Message**
120
121Connected NFC tag running state is abnormal in service.
122
123**Description**
124
125An error occurs when the service logic of the active NFC tag is executed.
126
127**Possible Causes**
1281. The parameter values of the active NFC tag do not match the API called.
1292. The active NFC tag chip does not respond within the specified time or returns an error status.
130
131**Solution**
1321. Check that the active NFC tag parameters match the API called.
1332. Touch and read the card again.
134