Document Reference No.: ES_000008
S1-A-7001 RS232 to 1-Port CANbus Adapter User Guide
Version 1.2
Clearance No.: ES #03
©2009-10 EasySync Ltd.
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9
Troubleshooting
9.1
Hardware
If the Yellow LED is not lit when plugged into CANbus connector, check the following:
-
All cables are properly inserted and secured
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External power supply is ON and in the range of +6VDC to +15VDC
If communication appears to be functioning to the S1-A-7001, but CAN communication is not functioning,
the CANbus cables may need checked:
-
Termination: The CANbus network requires 120ohm termination at the furthest points on the
network. If additional termination resistors are present through the CANbus network or if one of the
termination resistors is missing at one of the ends, the CANbus network will not communicate.
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Twisted Pair: The CANbus network consists of a differential pair of signals which greatly reduce noise
on the signals. Failure to use twisted pair may cause erroneous communications, or cause the
CANbus network to completely fail communications.
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Polarity: The CANbus network consists of a CAN_H and CAN_L signal. Care must be taken to follow
the polarity. Always connect CAN_H to CAN_H, and CAN_L to CAN_L.
Ensure the CANbus network is only connected to the S1-A-7001
after
connection to a RS232 port. See
for default LED power-up patterns. The CANbus network can remain connected through
system reboots.
