The coolant light is almost certainly a bad coolant level sensor - I've had this problem with almost every W124 I've owned.

The level sensor begins to leak and the contact pins are semi-shorted due to the resistance of the coolant that has leaked into the connector. This results in a "dim" light - you can verify this is really the problem by pulling the connector on the level sensor and drying the contacts on the connector - the light should go out.

There have been discussions about oil-level warning lights - most of the time the problem is related to the level sensor in the oil pan.

Not sure about the outside temp indicator.