If your vehicle has been out of service for 30+ cumulative calendar days for warranty repairs, the Tanner presumption applies and you may qualify for a buyback.
California’s lemon law contains two parallel triggers for the Tanner Act presumption: the four-attempt rule for recurring defects, and the 30-day rule for extended time out of service. The 30-day rule is often overlooked but is equally powerful — and it can apply even when no single defect has been attempted four times.
Under Cal. Civ. Code § 1793.22(b)(2), a vehicle is presumed to be a lemon if it has been “out of service by reason of repair of nonconformities by the manufacturer or its agents for a cumulative total of more than 30 calendar days” during the applicable warranty period. This presumption arises independently of how many repair attempts have been made for any single defect — it is a standalone trigger based purely on cumulative time out of service.
“Out of service” means the vehicle is not in your possession and is at a dealership or repair facility for warranty-related repairs. The count begins on the day you drop the vehicle off and ends on the day it is returned to you. Weekends and holidays that fall within the repair period count — you do not get only business days. Days do not have to be consecutive; they accumulate across all warranty repair visits throughout the warranty period.
Example: Your car spent 12 days in the shop in January for a transmission issue, 8 days in March for an electrical problem, 7 days in July for a recurring AC defect, and 6 days in September for an engine oil leak. Total: 33 days out of service. Even though no single defect reached four attempts, you are over the 30-day threshold and the Tanner presumption applies.
This is the key distinction between the two Tanner triggers. The four-attempt rule requires the same defect to be repaired four times. The 30-day rule has no such restriction — days spent on any combination of warranty defects accumulate. If your vehicle has had a series of different problems that each required extended repair time, the 30-day rule may be your most powerful argument even if no single defect was attempted repeatedly.
Every repair order issued by a dealership should show a “date in” and “date out” (or “date returned”). These are your primary evidence for calculating days out of service. If a dealer kept your car for two weeks but the repair order only shows a single date, follow up and ask for documentation showing when the car actually came in and when it was ready. You are entitled to accurate records.
Keep a simple log: every time your car goes to the dealer, note the drop-off date and pickup date. Add up the days. If you are approaching 30, contact a lemon law attorney immediately — you may already have crossed the threshold.
A question that frequently arises: if the dealer provides a loaner car while yours is in the shop, do those days still count toward the 30-day threshold? The answer is yes. Whether or not you had alternative transportation during the repair period, the days your vehicle is out of your possession for warranty repair count toward the 30-day total. The loaner car is not your car — you are still being deprived of the vehicle you paid for.
Like the four-attempt trigger, invoking the 30-day presumption in litigation technically requires that the consumer notify the manufacturer of a final repair opportunity after the threshold is met. Your lemon law attorney will handle this notice as part of the demand process — sending a written demand to the manufacturer that simultaneously provides statutory notice and demands a buyback or replacement.
If your car has been in the shop for a total of 30 days or more for warranty repairs — even across multiple different issues — you should consult a lemon law attorney today. Many clients who think they do not have a case because they have “only” had two or three repair attempts for each defect are surprised to discover they crossed the 30-day threshold months ago. The calculation is simple arithmetic, and the remedy — a full buyback with attorney fees paid by the manufacturer — can be significant.