Dim Orange charging light

Original Apple 85w charger, clean like new, no damage or bends on the cable, the Pins on the connector and the charging port are spotless clean but the orange light when charging is quite dim (Green light is bright OK), It is charging the MacBook as per normal and is not getting hot. I tested the MacBook with another charger and it is much brighter (normal). The battery is getting old and will be replaced when the replace now message comes (910 CC 74%). What is possibly causing this? Dying charger?