The California Lemon Law Presumption

What the Presumption Does

A presumption is a procedural shortcut. Once the consumer establishes that one of the three thresholds is met, the law presumes the manufacturer has had its reasonable number of attempts — and the consumer is entitled to a buyback or replacement under § 1793.2(d)(2) unless the manufacturer rebuts the presumption with admissible evidence.

The presumption is rebuttable, not conclusive — but in practice, when consumers satisfy a Tanner threshold and have clean repair-order documentation, manufacturer rebuttal is rare and unsuccessful.

The Three Thresholds

1. Four or more repair attempts for the same nonconformity

The most common path to the presumption. “Same nonconformity” means the same defect or substantially similar defects in the same system. Four repair orders documenting an intermittent transmission shudder qualify; two for transmission shudder and two for an unrelated electrical issue do not.

Each visit to an authorized service facility counts as one attempt, even if no parts were replaced. The dealer’s failure to reproduce the defect on a given visit still counts.

2. Two or more attempts for a serious safety defect

“Defect likely to cause death or serious bodily injury” is read broadly by California courts. Brake failures, sudden acceleration, steering loss, airbag malfunctions, fuel leaks, and stalling at highway speed all qualify. Two documented attempts at the same safety defect trigger the presumption.

3. 30 or more cumulative days out of service for repair

Days are counted cumulatively, not consecutively — a vehicle in for 10 days, then 12, then 9 totals 31 and meets the threshold. Days run from drop-off until pickup. Loaner-vehicle days count against the manufacturer.

Parts-on-backorder delays count. Delays caused by the consumer (failure to pick up after repair completion) do not.

The 18 Months / 18,000 Mile Window

All three thresholds must be reached within either:

• 18 months from the date the vehicle was delivered to the original buyer, or
• 18,000 miles of operation,

whichever comes first. The clock and odometer start on the delivery date.

An additional repair attempt after the 18/18,000 cutoff does not destroy the presumption if the threshold was already met inside the window. Conversely, repair attempts occurring partially inside and partially outside the window still count toward the threshold if the defect first appeared inside the window.

What If You’re Outside the Presumption Window?

The presumption is one path to a Song-Beverly claim, not the only path. Civil Code § 1793.2 itself requires the manufacturer to repair within a “reasonable number of attempts” — and that standard applies regardless of the 18/18,000 window.

Outside the window, the consumer must prove “reasonable number” as a question of fact. The evidence is the same — repair orders, technician notes, technical service bulletins, manufacturer correspondence — and California juries routinely find for consumers on facts that would have triggered the presumption inside the window.

Many successful lemon law claims involve vehicles at 25,000–50,000 miles or 2–3 years old. Do not assume you are barred merely because you are past 18,000 miles or 18 months.

Manufacturer Notice Requirement

Under § 1793.22(b)(3), the lemon law presumption applies only if the manufacturer has been given the opportunity to make a final repair attempt after notice. The notice requirement is satisfied if:

• The manufacturer (not the dealer) was notified of the defect through written notice or its established consumer-affairs process, and
• The manufacturer was given a reasonable opportunity for a final repair attempt.

This notice requirement is procedural and easily satisfied. A California lemon law attorney serves the notice as part of the standard pre-litigation workflow.

How Manufacturers Try to Rebut the Presumption

Common manufacturer defenses include:

• Consumer abuse or neglect. Argument that the defect was caused by improper use, off-road operation, modifications, or skipped maintenance. Usually fails when documented properly.
• Inability to reproduce the defect. Argument that the consumer reported a problem the dealer could not verify. California courts have held that repair-order documentation of a complaint itself is sufficient.
• De minimis impairment. Argument that the defect did not substantially impair use, value, or safety. Fact-intensive; rarely succeeds for safety defects.

Repair-order language is the battleground. See documenting defects for what to do at the dealer.

What to Do If You Think You’re at a Threshold

1. Stop assuming the dealer will fix it. Each additional attempt is evidence — but it is also delay.
2. Gather every repair order. Including any handwritten notes from service writers.
3. Document the days out of service. Loaner paperwork, rideshare receipts, calendar entries.
4. Get a free case review. A California lemon law attorney can tell you in minutes whether you have crossed a Tanner threshold.