[Richard L]

Good find.

Next step check:

4. The pump is running under manual test linked.
5. If there is no pump activation
6. Check the fuse between the 15A relay and pump.
7. Check if there is 12V across the thin red and blue wire under the relay.
8. If there is 12V present and the pump is not running, bridge the two thick red wires.
9. If the pump comes on, you have a faulty relay
10 If the pump still does not come on after bridge the two thick red wires
11. Check if there is 12V across the two-pin connector to the pump.
12. Check the black wire is grounded properly.

That is all for now.