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BLOCKsignalling
www.blocksignalling.co.uk
Troubleshooting
If the module is not functioning as expected, please follow these diagnostic tests.
1. The led on the module does not light. Disconnect all the connections except
the power supply and connect a link between the A and K terminals. If it now
lights, recheck the connections to the IR sensor carefully. If it still does not
light, replace your power supply with a 9V battery to check if your power
supply is causing the issue.
2. When the module is switched on, none of the signal leds light. This module
requires common-cathode signals. If yours are common anode, they will not
work with the module. We do manufacture a module for common-anode
signals.
3. The module shows a green signal for 1 second, then switches to red and
stays there. Light may be escaping from the rear of the sensor and reflecting
off adjacent material. Use black tape around the rear of the sensor to prevent
light leakage or reduce the sensitivity of the sensor by adjusting memory
setting 9.
4. With 2-aspect signals, there are times when neither is lit. The module needs
to be programmed for 2-aspect signals. If it is programmed for 3- or 4- aspect
signals, there will be times when yellow (and double yellow) indications would
be shown.
