User's Manual

301UM0031_01 TD136 Enhanced Vehicle Detector User Manual Page: 21 of 29
8. CUSTOMER FAULT ANALYSIS
8.1 Fault Finding
FAULT CAUSED BY REMEDY
Red LED does not glow on
power up.
If the indicator is off then there
is a fault on the power
connection to the unit.
Check power feed to the unit.
After the initial tune period the
Green LED flashes (ON for 1
second and OFF for ½
second)
Unit cannot tune to the loop
due to faulty loop or feeder
connection.
Loop may be too small or too
large.
Faulty detector unit.
Check loop installation and
connections.
Recut as per installation
instructions.
Replace unit.
After tuning, the loop output
LED flashes intermittently and
the relay chatters.
The loop is getting spurious
detects due to:
a) Crosstalk with adjacent
detector.
b) Faulty loop or feeder
connection.
a) Change frequency
setting.
b) Check that the feeders are
correctly connected and
adequately twisted.