I've noticed the LCD display on my Vetta RT77 and Cateye Astrale turning dark when the temperature is below 50-55 degrees. New batteries didn't help.
Makes it hard to read in the shade of overhanging trees or when there's little sunlight (morning or evening).
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The Lord is merciful and gracious, slow to anger and abounding in steadfast love. - Psalm 103:8
I am a cyclist. I am not the fastest or the fittest. But I will get to where I'm going with a smile on my face.