I copied this from ford trucks forum. The message should appear every 600 hours of operation.
From:
http://www.ford-trucks.com/forums/1064454-check-coolant-additive.html
You clear in in the INFO screen. Should tell you how to in the owners manual.
Also, here is how to test your coolant:
1st. Check for the presence of nitrates in your coolant (There should be none) with Rotunda test kit number 328-00001. If there is, you have to flush and refill.
2nd. Check the percent of glycol in the coolant. use the same rotunda kit for this as well. Should be between 40-60%. If this is not the case, you have the flush the cooling system.
3rd. Check the Reverse Coolant Alkalinity. You need Rotunda test kit number 328-00008.*
If its low, you must add some stuff included with the kit, if its high, you add another stuff to the coolant. If its ok, move to next step.
4th. Check coolant corrosion ability. You need rotunda kit number 328-00008, which is the same as last. Follow the instructions included in the kit. If it does not pass, then you have to add a bottle of*revitalizer. Ford part number vc-12. Otherwise your coolant is good to go.*
WOW. I would charge $75 for this too.*
Link to supplies
https://rotunda.spx.com/en-US/Pages/...x?itemID=16878
https://rotunda.spx.com/en-US/Pages/...x?itemID=22023
It should also be noted, those without the 4.2" LCD fancy screen will not get a service warning for checking coolant. Follow your maintenance schedule to stay on top of it. $70 is worth the ability to test your coolant for years to come.