BA II Plus Reset Guide and Every Error Code Explained (Error 1-7)

In this tutorial

The four levels of clearing: CLR WORK, CLR TVM, memory reset, full reset
Example 1: the exam-room full reset
Example 2: clearing a worksheet after an error
Every error code from Error 1 to Error 7
When an error means "recheck the inputs," not "clear everything"
How to avoid the common error triggers

Clear, don't panic: the four clearing tools

Tool	Keystrokes	What it clears
CLR WORK	`[2nd]` then `[CLR WORK]`	The worksheet currently on screen (cash flows, AMORT, DEPR, DATE, STAT data, Bond worksheet, ...). Keeps TVM and settings.
CLR TVM	`[2nd]` then `[CLR TVM]`	N, I/Y, PV, PMT, FV. Keeps worksheets and format settings.
Memory reset	`[2nd]` then `[RESET]`, then `↑` until `MEM?`, then `[ENTER]`	All worksheet values and registers, but keeps format settings (decimals, AOS, P/Y, date format).
Full reset	`[2nd]` then `[RESET]`, then `[ENTER]`	Everything: worksheets, TVM, registers and every format setting back to factory defaults (P/Y = 1, Chn, 2 decimals, US date format).

The [RESET] key is the second function of [+/−]. Pressing [2nd] then [RESET] shows RST?; [ENTER] confirms a full reset, ↑ switches the prompt to MEM? for the memory-only reset.

Example 1: the exam-room full reset

Before a timed session, reset to a known state and restore your preferred format:

Press [2nd] then [RESET]. The display shows RST?.
Press [ENTER]. The calculator beeps and returns to a factory state.
Press [2nd] then [FORMAT]. The display shows DEC=2.
Enter 9, press [ENTER] — the display now keeps 9 decimals.
Press ↓ until Chn appears, press [2nd] then [SET] to switch to AOS (standard algebraic order).
Press ↓ to the P/Y line, press [2nd] then [QUIT].
Confirm P/Y and C/Y are 1 by pressing [2nd] then [P/Y]; the display reads P/Y=1.00 and C/Y=1.00. Press [2nd] then [QUIT].

You now have a clean, exam-ready calculator. This is the reset routine in the basics tutorial, condensed into seven keystroke groups.

Example 2: clearing a worksheet after an error

Suppose the Amortization worksheet returns an unexpected balance. Recover without touching the rest of the calculator:

Press [2nd] then [AMORT] — you are back in the worksheet that errored.
Press [2nd] then [CLR WORK]. The P1/P2/BAL/PRN/INT fields reset to defaults.
Re-enter the two values that matter (P1, P2) and scroll down — INT and PRN recompute.

Never full-reset for a single worksheet mistake: CLR WORK is faster and keeps your TVM inputs intact.

Every error code, explained

The BA II Plus has seven error codes. None of them damage data — every error leaves the calculator usable after you press [CE/C] (or [ON] on newer models) to clear the message.

Error 1 — invalid key combination

Trigger: pressing [2nd] followed by a key that has no second function, or two operation keys in a row (e.g. [2nd] then [+/-] expecting RESET but accidentally pressing [ENTER] twice).

Fix: press [CE/C] and continue. If you intended a worksheet, press the worksheet key first, then [2nd] and [CLR WORK].

Error 2 — statistics calculation error

Trigger: computing a statistic that is undefined for the current data — for example, pressing [CPT] for X' or Y' before any data pairs are entered, or a division by zero in a regression with constant x-values.

Fix: clear DATA with [2nd] then [7], then [2nd] then [CLR WORK], re-enter the pairs, and retry. The linear regression tutorial shows the data-entry routine.

Error 3 — IRR calculation error

Trigger: the cash-flow stream has no sign change (all inflows or all outflows), or the calculator cannot converge on a rate — a common case with the 32-cash-flow limit or unusual patterns.

Fix: review the signs of CFo, C01... — there must be at least one positive and one negative flow. If a sign is right, try narrowing to the flows around the sign change, or use NPV at a test rate to confirm the stream behaves. See the NPV/IRR section in the advanced functions tutorial.

Error 4 — storage register error

Trigger: trying to store into or recall a register that does not exist — for example, [STO] then [0] is fine, but [STO] followed by a non-register key (like [CPT]) is not.

Fix: press [CE/C], then use only [0] through [9] and [.] as storage-register names. Memory functions are covered in the basics tutorial.

Error 5 — TVM or NPV calculation error

Trigger: inconsistent TVM inputs — the classic exam trap is solving for I/Y with PV = PMT = FV = 0, or an NPV where the discount rate makes the math impossible with the entered sign pattern.

Fix: check that at least three of the four values N, PV, PMT, FV are non-zero and that signs follow the cash-flow convention (one negative, the rest positive). Press [2nd] then [CLR TVM] and re-enter. The basics tutorial and the NPV/IRR part of the advanced functions tutorial both show the sign conventions.

Error 6 — amortization or depreciation worksheet error

Trigger: values outside a worksheet's domain — for example, P1 or P2 beyond the number of payments in AMORT, or YR greater than LIF in DEPR.

Fix: press [CE/C], reopen the worksheet, and confirm every entered field. For AMORT, keep P1 ≤ P2 ≤ N. For DEPR, keep YR between 1 and LIF. The amortization tutorial and depreciation tutorial list the field limits.

Error 7 — invalid date or Bond worksheet error

Trigger: a date the calculator rejects — month outside 1–12, day outside 1–31, an impossible day like February 30 — or a Bond worksheet with an invalid settlement/maturity pairing (maturity before settlement, or the 2nd [SET] coupon-frequency setting left inconsistent).

Fix: verify the MM.DDYY entry (single-digit days need a leading zero: March 5 is 3.0526), then check settlement < maturity in the Bond worksheet. The date worksheet tutorial and the bond section of the advanced functions tutorial cover both.

When an error is a hint, not a bug

The most useful habit: when an error appears, read it as a diagnostic.

Error 5 in a TVM solve almost always means a missing or zero input — never happens on a well-posed exam question.
Error 3 on IRR means re-examine the cash-flow signs, not "the calculator is broken."
Error 7 on a bond means the dates themselves are inconsistent — fix the date, not the calculator.

Only a full reset changes format settings. For everything else, [CE/C] + CLR WORK gets you back to work in seconds.