Why won't my chronograph second hand go back to zero?

Two answers circulate for this question. Forum threads say pull the crown and press a pusher until the hand reaches 12; watchmakers say an off-zero hand needs the case opened. The first is true of almost every quartz chronograph and impossible on a mechanical one. The second is true of mechanical ones and needlessly expensive advice for quartz. If the case back says quartz or the watch takes a battery, read on. If it winds, or its small seconds sweeps smoothly, skip to the mechanical section.

Why a quartz chronograph loses its zero

On a quartz chronograph motors step the hands forward and the circuit keeps count of where it has sent them. Press reset and it drives the hand to the position it has on record as zero. Nothing physical stops the hand at 12, so if hand and record disagree, the hand returns faithfully to the wrong place every time.

Two events cause that disagreement, and the manuals name both. Citizen's B51* manual says the zero position "may rarely shift out of position after replacing the battery or after the watch has been subjected to a strong shock". The H50* manual names the same two: a hand that does not return to 0 when reset, or one that "has shifted out of position due to strong impact". Citizen's 0510 family manual goes further for battery changes: the procedure is "required because the chronograph hands may not return to the '0' position when the chronograph is reset after changing the battery".

Miyota's manuals show the mechanism from the other side. The procedure ends when you push the crown home, and Miyota warns that if you do that while the hand is still moving, "it stops on the way" and "its position is recognized as zero position". Wherever the hand is when the crown goes home becomes zero: the fix, and the commonest way to make it worse.

The reset procedure, caliber by caliber

Find your caliber first. On a Citizen, the first four characters of the case number engraved on the case back are the movement number, according to Citizen's own manual: a back reading 0510-S123456 holds an 0510. Miyota movements turn up under many brand names, so check the brand's spec sheet. The letters A and B are each maker's labels, not positions: Miyota's FS diagram puts A above B, while Citizen's B61* manual calls the upper right pusher B and the lower right A. Check the diagram in your own manual.

Three things in that table catch people out. "Press the top pusher" is not universal advice: Miyota and Citizen's B51* step with A, Citizen's 0510 family, B61* and H50* with B. The two Citizens with a mode switch ignore a short press of B until it has been held for 3 seconds, so an owner who taps it and sees nothing has not found a fault. And most Citizen procedures disturb the time display, so the last step is setting the time again.

Doing it without making it worse

1. Unscrew first. Citizen's H50* manual says to loosen a screw-lock crown before operating it, and the B61* manual reminds you to screw the screw-down crown and pushers back afterwards because "water may enter your watch".
2. Charge a solar watch first. On the H50*, zeroing "cannot be performed" during 2-second movement. Put an Eco-Drive in daylight until it is back to 1-second movement; our answer on how long a solar watch takes to charge gives the times.
3. Pull the crown to the time-setting position.
4. Enter the mode if your caliber needs it, then step the hand: hold the pusher to get close, single presses to finish.
5. Stop when the hand is exactly on 12, looking straight down at the dial, not at an angle.
6. Wait until the hand is still, then push the crown home. On a Miyota this is the step that decides what zero means.
7. Test it: start, stop, reset. If the hand returns to 12, set the time and screw everything back down.

Seiko's VK series is the exception

The Seiko manual for the VK63, VK67, VK68, VK73 and VK83, five calibers in one booklet, is the only one we read that tells you not to bother. "It is not necessary to set the chronograph hands after the battery is exchanged," it says. If the hand positions are wrong, it gives the ordinary sequence, start, stop and reset, after which "all the chronograph hands will be reset to '0' position".

Its step after a battery change is for the circuit, not the hands: crown at the second click, press B for two seconds, release, push the crown home. The small seconds then moves at two-second intervals for 10 seconds "as a demonstration", which is not a low-battery warning. The VK83 differs only in its counters: a 20-minute counter, and B before A to restart after a full measurement. The reset is the same for all five.

Mechanical chronographs have no reset procedure

A mechanical chronograph returns to zero by geometry, not by memory. ETA's technical communication for the Valjoux 7750 (CT 7750, 24 August 2022) lists push-button B as "return to zero of chronograph" and describes the reset position as the one in which "the hammer makes contact with the heart-pieces". The hammer slides down each heart-shaped cam to the one position where it sits flat. Our chronograph guide walks through the parts.

So there is no stored zero to lose and no button sequence to restore one. If the hand stops off 12 after the hammer drops, either the hand has turned on its arbor, typically after a knock, or the hammer is not seating fully on the heart. Both are fixed with the movement out: ETA's uncasing sequence has the hands pulled off before the dial comes out, and it calls for a part holder with suitable supports when hands are refitted.

No pusher sequence helps, and on a non-flyback chronograph pressing reset while it runs does nothing, as our answer on what a chronograph is for explains. If the watch is due for service anyway, have it done then: a full chronograph service is indicatively $700 to $1,200 in the US before sales tax, as our service cost guide sets out. A hand refit alone is a much smaller job, so ask for a price before booking.

When the reset will not hold

The procedure fixes a lost record, not a slipping hand, a skipping gear or a motor that will not step. None of the manuals offers an owner step beyond zeroing, so these go to a service center. The signs:

• The hand zeroes correctly, then misses again within days with no knock or battery change between.
• The seconds hand returns to 12 but the minute counter does not, after you have completed every step for your caliber.
• In correction mode the pusher does not move the hand at all, on a charged watch or a fresh cell.

One case is not a fault at all. A pusher moves the hand one whole step, a second or a fifth of a second depending on caliber, so a hand pointing between two marks was pressed on slightly rotated, the same cosmetic question as a misaligned time hand, and only refitting it will change it.

If a quartz chronograph has stopped altogether, start with our stopped-quartz checklist rather than here. And if the next battery is the question, chronographs vary more than most: Miyota rates its 0S chronographs at five years on an SR927W and its FS family at two on an SR626SW, as our answer on how long a watch battery lasts details.