Do Seventh-day Adventists accept the Bible to be literally true?

Yes. They believe that the original authors were inspired by God. As the apostle Peter said, "Holy men of God spake as they were moved by the Holy Ghost."

Seventh-day Adventists, of course, know that there have been many translations of the Bible, but hold that the original intent of the inspired authors has come down unimpaired through the centuries. Because words change in meaning with the passage of time, occasional revisions of translations are desirable, but through them all the original message is clearly discernible and "the word of the Lord endureth forever."

Quoted from Arthur S. Maxwell in A Handbook of Denominations

The Holy Scriptures, Old and New Testaments,are the written Word of God, given by divine inspiration through holy men of God who spoke and wrote as they were moved by the Holy Spirit. In this Word, God has committed to man the knowledge necessary for salvation. The Holy Scriptures are the infallible revelation of His will. They are the standard of character, the test of experience, the authoritative revealer of doctrines, and the trustworthy record of God's acts in history. (2 Peter 1:20, 21; 2 Tim. 3:16, 17; Ps. 119:105; Prov. 30:5, 6; Isa. 8:20; John 17:17; 1 Thess. 2:13; Heb. 4:12.)

---A Biblical Exposition of 27 Fundamental Doctrines. Chapter 1.