Check coolant SCA (supplemental coolant additives) level

• A. At every service interval
• B. Only when service is changed
• C. When system feels cold
• D. Never

Answer: (A)

SCA levels are checked regularly as part of routine coolant maintenance because the supplemental coolant additive that protects against corrosion and cavitation can be depleted over time and with use. By testing the SCA concentration at every service, you ensure the coolant still has enough inhibitor to guard engine passages, water pump, and other metal surfaces. If the level is too low, you add the recommended amount to restore protection; if it’s too high, you follow the manufacturer's guidance to correct it. Checking only when a service changes or only when the system feels cold isn’t reliable, and never is obviously incorrect.