Toyota Grand Highlander: NHTSA Probe & CA Lemon Rights
NHTSA has opened a formal Defect Petition investigation — assigned investigation number DP26006 — into model year 2024, 2025, and 2026 Toyota Grand Highlander vehicles. The petition, filed on July 20, 2026, alleges that a fundamental design flaw in the vehicle’s front-end grille allows road debris and rocks to travel unimpeded into the vehicle’s heat exchangers, causing coolant leakage and sudden, unexpected loss of propulsion.
If you own or lease a 2024–2026 Toyota Grand Highlander in California, here is what you need to know about the investigation, the safety risk, and your legal rights under the Song-Beverly Consumer Warranty Act — California’s lemon law.
What Is NHTSA Investigating on the Toyota Grand Highlander?
According to NHTSA’s Office of Defects Investigation (ODI), the Defect Petition under investigation number DP26006 was filed on July 20, 2026. The petitioner — along with thirteen additional complainants whose reports were already on file with NHTSA — alleges the following sequence of events:
- Open grille apertures: The Grand Highlander’s front-end grille has large, open gaps with no protective screen or mesh between the grille opening and the vehicle’s heat exchangers behind it.
- Road debris intrusion: During ordinary, everyday driving, rocks and other road debris pass through those unprotected gaps and strike the heat exchangers.
- Coolant leakage: The debris impacts damage the heat exchangers, causing coolant to leak from the cooling system.
- Sudden loss of propulsion: Coolant loss leads to sudden, unexpected loss of propulsion — the vehicle loses power while in motion.
As of the date the investigation was opened, ODI had identified fourteen (14) complaints — thirteen from the public and one from the petitioner — alleging this specific failure pattern across 2024–2026 model year Grand Highlander vehicles. ODI will now evaluate whether these complaints are causally related to the alleged defect and conduct a technical review under 49 CFR Part 552.
The petition itself can be reviewed at NHTSA.gov under ODI number 11754975.
Why Sudden Loss of Propulsion Is a Serious Safety Risk
Sudden and unexpected loss of propulsion is not a mere inconvenience — it is a documented crash risk. When a vehicle abruptly loses power at highway speeds or in heavy traffic, the driver may lose the ability to:
- Maintain speed in the flow of traffic
- Complete a merge or lane change safely
- Clear an intersection
- Operate power-assisted steering or braking systems at full effectiveness
The safety consequences can range from rear-end collisions — as following vehicles have no warning the Grand Highlander is decelerating — to the vehicle becoming a stationary hazard in a lane of moving traffic.
This is precisely the type of defect that NHTSA takes seriously enough to open a formal petition investigation: an alleged design flaw that is reproducible under normal driving conditions and that creates a foreseeable risk of crash or injury.
California Toyota Grand Highlander Lemon Law: What Song-Beverly Requires
What the Song-Beverly Consumer Warranty Act Covers
California’s Song-Beverly Consumer Warranty Act (Civil Code §§ 1790–1795.8) is among the strongest consumer vehicle warranty protection laws in the United States. It applies to new motor vehicles — including SUVs like the Grand Highlander — purchased or leased primarily for personal, family, or household use in California and covered by a manufacturer’s express warranty.
Under Song-Beverly, if a new vehicle has a defect or nonconformity that substantially impairs the vehicle’s use, value, or safety, and the manufacturer or its authorized repair dealers are unable to repair the defect to conform to warranty after a reasonable number of repair attempts, the manufacturer is legally obligated to either:
- Repurchase (buy back) the vehicle — reimbursing the buyer for the purchase price, down payment, monthly payments made, registration fees, and incidental expenses, minus a mileage offset for use prior to the first repair attempt; or
- Replace the vehicle with a comparable new vehicle.
The owner or lessee gets to choose between repurchase and replacement.
What Counts as a “Reasonable Number” of Repair Attempts?
Song-Beverly does not require you to give the manufacturer unlimited chances to fix a dangerous defect. California courts apply a rebuttable presumption that a reasonable number of repair attempts has been exceeded when, within the warranty period:
- The same defect has been subject to repair four or more times and still exists; or
- The vehicle has been out of service for 30 or more cumulative days due to repair.
For defects that could cause death or serious bodily injury if the vehicle is driven, the threshold drops significantly — just two repair attempts can be sufficient to trigger the presumption under the statute.
A sudden loss of propulsion defect — where a moving vehicle unexpectedly loses power — is exactly the type of safety-critical failure that may meet this lower threshold. If a Toyota dealer has attempted to diagnose or repair heat exchanger damage or coolant loss on your Grand Highlander and the problem persists, you may already be in presumption territory.
Manufacturer’s Obligation to Act — and the Penalty for Refusing
Once the reasonable repair attempt threshold is met, Song-Beverly requires the manufacturer to promptly offer repurchase or replacement. If Toyota refuses to honor this obligation willfully — meaning it knew of its duty and chose not to comply — California law allows a court to award up to two times the amount of actual damages as a civil penalty on top of the full repurchase or replacement value.
Additionally, under Song-Beverly, attorney fees and costs are paid by the manufacturer, not by you. This means you can retain qualified California lemon law counsel at no out-of-pocket cost, removing one of the most common barriers consumers face when asserting their rights against a large automaker.
How an NHTSA Investigation Affects Your Lemon Law Claim
The opening of a formal NHTSA Defect Petition investigation is significant for Grand Highlander owners in several ways.
First, it establishes that the complaints about heat exchanger damage and loss of propulsion are being taken seriously at the federal level. An investigation opening is not a finding of a defect, but it is NHTSA’s formal acknowledgment that the petitioned issue warrants technical review.
Second, the investigation creates a public record. NHTSA complaint data, investigation records, and any technical service bulletins (TSBs) that Toyota may issue in connection with the investigation can all serve as supporting evidence in a Song-Beverly claim. California lemon law attorneys routinely use NHTSA complaint data to demonstrate a pattern of defects affecting a vehicle model — which strengthens individual claims.
Third, if NHTSA ultimately upgrades the investigation to a full engineering analysis or orders a recall, that timeline may not align with your legal deadlines. California’s statute of limitations for Song-Beverly claims is four years from the date the defect was discovered — but waiting for a recall to be issued is not a strategy that protects your rights. The time to act is while your vehicle is still under its original manufacturer’s warranty and before repair attempts accumulate without resolution.
For a deeper look at how recalls and lemon law claims interact under California law, see our guide: California Lemon Law vs. Recall Protection: When Both Apply to Your Defective Vehicle.
California Toyota Grand Highlander Lemon Law: Steps to Take Now
H3: Document Every Service Visit
If your 2024, 2025, or 2026 Toyota Grand Highlander has experienced coolant leakage, heat exchanger damage, loss of propulsion, or any related warning lights or symptoms, your most important immediate action is documentation.
- Save every repair order — not just the summary invoice, but the full repair order that includes the technician’s notes, the mileage at drop-off and pick-up, and the date.
- Describe the symptom in your own words when you bring the vehicle in. The repair order should reflect the concern as you reported it, not just the technician’s diagnosis.
- Record every out-of-service day. Under Song-Beverly, the 30-day cumulative out-of-service presumption counts calendar days the vehicle is at the dealership for warranty repair — even if the dealer is waiting on parts.
- Keep records of all communications with Toyota Motor Sales U.S.A. or its customer service representatives.
For a complete documentation checklist, see our guide: How to Document Your Lemon Law Case.
H3: Understand That You Do Not Have to Keep Attempting Repairs Indefinitely
One of the most common misconceptions Grand Highlander owners may have is that they must keep bringing their vehicle back for repair indefinitely before they have any legal recourse. Song-Beverly is explicit: the manufacturer is entitled to a reasonable number of attempts — not an unlimited number. Once that threshold is met and the defect remains, your right to repurchase or replacement has accrued.
Manufacturers and their dealership networks sometimes employ delay tactics — attributing the problem to road conditions, telling owners the damage is not covered under warranty, or scheduling repeated inspections without performing substantive repairs. Recognizing these tactics early is essential. For more on this, see: California Lemon Law: How to Recognize Manufacturer Bad Faith Tactics.
H3: Consult a California Lemon Law Attorney Before Accepting Any Offer
If Toyota or an authorized Toyota dealer has offered you any form of goodwill repair, extended warranty, or partial reimbursement in connection with heat exchanger or coolant issues on your Grand Highlander, do not accept it without speaking to a California lemon law attorney first. Accepting a partial settlement may affect your ability to pursue a full Song-Beverly repurchase or replacement claim.
Because Song-Beverly requires Toyota to pay your attorney’s fees if you prevail, there is no financial reason to navigate this process alone. A qualified California lemon law attorney can evaluate your repair history, assess whether the statutory thresholds have been met, and pursue the full remedy the law provides — including the civil penalty if Toyota’s refusal to comply is willful.
For background on how Song-Beverly attorney fee provisions work in practice, see: California Lemon Law Attorney Fees: Who Pays Legal Costs?.
What Toyota May Be Required to Do
The NHTSA investigation under DP26006 is in its early stages — ODI is currently evaluating whether the fourteen complaints are causally related to the alleged design defect before deciding whether to grant or deny the petition. If the petition is granted, ODI would open a full engineering investigation, which could ultimately lead to a formal recall.
Regardless of how the federal investigation progresses, Toyota’s obligations to individual California consumers under the Song-Beverly Consumer Warranty Act exist independently of any recall. A recall does not replace your lemon law rights — it supplements them. If your Grand Highlander has already experienced the heat exchanger and propulsion loss defect described in the petition and has been in for repairs, your Song-Beverly claim may already be ripe, even before a recall is issued or denied.
For a broader overview of Toyota lemon law claims in California, including the Song-Beverly process and what Toyota is required to do under state law, visit our Toyota Tacoma Lemon Law guide for context on how California law applies to Toyota vehicles, and explore our Song-Beverly Consumer Warranty Act overview for a full explanation of your statutory rights.
Free California Lemon Law Consultation for Toyota Grand Highlander Owners
If you own or lease a 2024, 2025, or 2026 Toyota Grand Highlander in California and you have experienced heat exchanger damage, coolant leakage, unexpected loss of propulsion, or repeated service visits for related symptoms, you may have a viable Song-Beverly Consumer Warranty Act claim.
California law is on your side — and the manufacturer pays your legal fees if you prevail. You should not have to absorb the cost and safety risk of a vehicle defect that Toyota’s warranty is supposed to cover.
Contact us today for a free case evaluation. We represent California Grand Highlander owners in pursuing their full rights under the Song-Beverly Act — including repurchase, replacement, and civil penalties where Toyota’s conduct warrants them.