Troubleshooting
CAN Error Diagnostic Codes:
Similar codes are used with CAN vehicle module and CAN keypad.
The keypad uses back lighting and buzzer for communicating codes
while the vehicle module uses D16 and D17 LEDs.
1. At power up the CAN module will attempt to claim its address on
the CAN bus. After this, it turns on both LEDs for 1 second.
This “long blink" of the LEDs communicates a CPU reset and why:
One 1 second blink = normal power on
Two 1 second blinks = watchdog timer reset the CPU (this
indicates a software bug)
Three 1 second blinks = brownout reset. The power supply
fell below the 2.0V requirement.
2. After the long blinks, a series of "short blinks" indicate other errors
that may have occurred:
Two short blinks = CAN bus error. This means there is an
electrical problem with the CAN bus (possibly a problem
with bus termination), or simply that the I/O module is the
only node attached to the bus. If the I/O module is the only
CAN unit on the network, the CAN communication must be
disabled.
Three short blinks = the I/O module couldn't claim its CAN
address. This is probably because another I/O module on
the bus is set to the same function instance. This is
considered a fatal error so the I/O module will reset itself
and try again.
3. The keypad either provides one long beep followed by two(2)
short beeps or five(5) short beeps followed by a pause to indicate
a CAN bus error.
13
To Next Page
