S7-300 PLC运行中当机，报错信息：

Event 47 of 500:  Event ID 16# 3842
Module OK
Module type: Distributed I/0s
Input address:  8145
User information available
Diagnostic interrupt from substitute
Requested OB: Diagnostic interrupt OB (OB82)
OB not found, or disabled, or cannot be started in the in the current operating mode
External error, Outgoing event
04:06:19.208 AM  10/25/1996
(Coding: 16# 3842  FE52  C554  1FD1  0063  0000)

Event 48 of 500:  Event ID 16# 5371
Distributed I/Os: End of the synchronization with a DP master/IO controller   on slot    2
Number of distributed stations:  45
Incoming event
04:06:19.198 AM  10/25/1996
(Coding: 16# 5371  FF02  C150  002D  0000  0000)

Event 49 of 500:  Event ID 16# 4548
STOP due to I/O management
Previous mode: RUN
Requested mode: STOP (internal)
Internal error, Incoming event
04:06:17.424 AM  10/25/1996
(Coding: 16# 4548  FF84  C000  0000  8021  0000)

Event 50 of 500:  Event ID 16# 38C4
Distributed I/Os: station return
Address of the affected DP slave: station number:    4
DP master system ID:      1
Log. base address of the DP slave: Input address:  8187
Log. base address of the DP master:   8191
Requested OB: Rack failure OB (OB86)
Priority class: 26
External error, Outgoing event
11:17:28.622 PM  10/24/1996
(Coding: 16# 38C4  1A56  C054  1FFF  1FFB  0104)

Event 51 of 500:  Event ID 16# 2942
I/O access error, reading
P area, word access, Access address:    266
Requested OB: I/O access error OB (OB122)
Priority class:  1
External error, Incoming event
11:17:28.565 PM  10/24/1996
(Coding: 16# 2942  017A  0020  010A  0000  0000)

请大神指点，谢谢。