2006 Toyota Highlander Problems: 2 Issues Every Owner Should Know

2006 Toyota Highlander Problems: 2 Issues Every Owner Should Know | Au7o

All 2 Known Issues

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Community Reported

1,200 owners

On the 2006-2013 Toyota Highlander, highlander Hybrid NiMH battery packs degrade over time, with individual cells failing after 8-12 years or 150,000+ miles. Failed cells cause reduced fuel economy, loss of hybrid assist, and eventual inability to start the vehicle.

This issue also affects: BMW 8 Series, BMW i3, BMW M3

Common Symptoms

Triangle warning light on dashboard
Reduced fuel economy
Loss of EV mode and hybrid assist
P0A80 Replace Hybrid Battery Pack code
Vehicle struggles to start

How to Fix

Replace the hybrid battery pack. OEM replacement from Toyota is $3,500-$5,500 installed. Refurbished packs from specialists like Green Bean Battery ($1,500-$2,500) or Dorman remanufactured (part 587-004) are more affordable. Individual cell replacement is possible for DIY owners using load-tested cells.

What Owners Are Using

Parts and tips from 1,200+ owners who fixed this issue

Tip
Tip
UpgradeHigh-performance AGM battery with excellent cold cranking amps and deep cycle capability (Optima RedTop AGM Battery)
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UpgradeOEM-quality replacement battery with reliable performance (ACDelco Professional AGM Battery)
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UpgradeAutomatic battery maintainer to prevent parasitic drain issues during storage (Battery Tender Junior 12V Battery Charger Maintainer)
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Typical repair cost:$1,500 - $5,500

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1,200+ owners have reported this issue

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Community Reported

High Confidence1,200 reportsLast reported by owners Feb 2026Reviewed Feb 2026

On the 2001-2007 Toyota Highlander 2.4L 2AZ-FE, the 2001-2007 Highlander with the 2.4L 2AZ-FE 4-cylinder engine suffers from a design flaw where the aluminum head bolt threads strip out of the engine block. The plastic intake manifold traps heat against the block, causing thermal fatigue of the aluminum threads. This leads to head gasket failure, coolant leaks, and overheating. In severe cases, the stripped threads make a simple head gasket replacement impossible, requiring thread repair inserts (Time-Serts) or complete engine replacement. This is a known issue across Toyota vehicles using the 2AZ-FE engine.

This issue also affects: Citroën C3, Hyundai Santa Fe, Hyundai Tucson

Common Symptoms

Coolant loss without visible external leaks
White sweet-smelling exhaust smoke
Engine overheating
Chocolate milk appearance of oil (coolant mixing)
Oil level higher than normal
Rough running or hard starting when cold
Coolant bubbling in overflow tank

How to Fix

What Owners Are Using

Parts and tips from 0+ owners who fixed this issue

UpgradeMulti-layer steel head gasket set for a reliable, long-lasting seal (Fel-Pro Head Gasket Set)
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UpgradeHigh-strength head studs provide even clamping force and prevent repeat failures (ARP Head Stud Kit)
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Typical repair cost:$2,500 - $5,000

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0+ owners have reported this issue

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Community Reported

Medium Confidence0 reportsLast reported by owners Invalid DateReviewed Invalid Date

⚠️NHTSA Recalls12 recalls

SEATS

Toyota is recalling certain model year 2013 Highlander vehicles manufactured March 13, 2013, through August 6, 2013. In the affected vehicles, the second row left hand seat may not lock in place when positioned in the forward front or second adjusting position. As such, the vehicles do not conform to Federal Motor Vehicle Safety Standard (FMVSS) number 207, "Seating Systems."

Campaign #14V14800027/03/2014

EQUIPMENT:OTHER:LABELS

Southeast Toyota is recalling certain model year 2008 and 2010-2013 Toyota Tundra, 2010-2012 Rav4, 2012 Toyota Sequoia, 2010-2011 Toyota Corolla, 2010-2011 Toyota Camry and Camry Hybrid, 2010-2013 Toyota Highlander and Highlander Hybrid, 2010-2013 Toyota FJ Cruiser, 2011 Toyota Land Cruiser, 2010-2013 Toyota Venza, 2010-2011 Toyota 4Runner, 2010-2013 Toyota Tacoma, 2011-2012 Toyota Sienna, 2012 Toyota Prius, 2013 Scion FR-S, 2011 Scion XD, 2011 Scion XB, and 2012 Scion TC vehicles. These vehicles were sold with labels that were outside the allowable one percent of accuracy of actual weight added. Thus, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) Number 110, "Tire Selection and Rims."

Campaign #13V12300009/04/2013

AIR BAGS:FRONTAL:SENSOR/CONTROL MODULE-INACTIVE

Southeast Toyota Distributors, LLC (SET) is recalling certain models interspersed through model years 2009 through 2013 as follows: model year 2009-2012 Tacoma, 4Runner, Camry, Camry Hybrid, Prius, and RAV4; model year 2009-2010 Avalon, FJ Cruiser, and Highlander Hybrid; model year 2010-2013 model year Corolla, Sienna and Tundra; model year 2009-2013 Highlander and Venza; model year 2012 Prius V; and model year 2010-2012 Sequoia. During modification by SET to include accessories such as leather seat covers, seat heaters or headrest DVD systems, these vehicles may not have had the passenger seat occupant sensing system calibration tested. Without passing the calibration test, the occupant sensing system may not operate as designed.

Campaign #13V01400016/01/2013

SEATS:FRONT ASSEMBLY:SEAT HEATER/COOLER

Southeast Toyota Distributors, LLC (SET) is recalling certain 2005-2011 4Runner, Highlander, Sequoia, and Sienna, 2005-2010 Avalon and Tundra, 2006-2008 Camry Solara, 2006-2010 Highlander hybrid, 2006-2011 Rav4 and Tacoma, 2007-2010 FJ Cruiser, 2007-2011 Camry hybrid, 2009-2010 Venza, 2010-2012 Prius, 1988-1990 and 2005-2010 Camry, and 1989 and 2009-2010 Corolla vehicles equipped with aftermarket accessory seat heaters with a copper strand heating element. The electrical wiring in the seat heaters may be damaged when the seat cushion is compressed.

Campaign #16V39600002/06/2016

SEATS:FRONT ASSEMBLY:SEAT HEATER/COOLER

Southeast Toyota Distributors, LLC (SET) is recalling certain model year 2010-2011 Prius and Corolla, 2009-2011 Venza, 2006-2010 Avalon, 2007-2010 FJ Cruiser, 2005-2011 Sienna and Sequoia, 2006-2011 Tacoma 4x2 and 4x4, Camry, Highlander, Tundra 4x2 and 4x4, and 2007-2011 Rav4 and 4Runner. The affected vehicles may experience compression of the seat cushion which may damage the seat heater wiring.

Campaign #14V74300019/11/2014

+ 7 more recalls. Check all on NHTSA.gov

Enter your VIN at NHTSA.gov to check recalls specific to your vehicle.

Frequently Asked Questions

What are the most common Toyota Highlander problems?

According to Au7o's analysis of 1,200+ owner reports, the 2006-2006 Toyota Highlander has 2 documented issues. The most frequently reported are: Hybrid Battery Pack Degradation and Failure, 2.4L 2AZ-FE Head Gasket and Head Bolt Thread Failure. Of these, 2 are rated critical and should be addressed promptly.

Is the Toyota Highlander reliable?

The 2006-2006 Toyota Highlander has 2 known issues documented across 1,200+ owner reports. 2 issues are rated critical: Hybrid Battery Pack Degradation and Failure and 2.4L 2AZ-FE Head Gasket and Head Bolt Thread Failure. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

How much does it cost to fix common Toyota Highlander problems?

Repair costs for known Toyota Highlander issues range from $1,500 to $5,500, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Hybrid Battery Pack Degradation and Failure, typically costs $1,500-$5,500 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

What is the 2006-2013 Toyota Highlander Hybrid Battery Pack Degradation and Failure?

Highlander Hybrid NiMH battery packs degrade over time, with individual cells failing after 8-12 years or 150,000+ miles. Failed cells cause reduced fuel economy, loss of hybrid assist, and eventual inability to start the vehicle. Repairs typically run $1,500-$5,500. Severity: high.

What is the 2001-2007 Toyota Highlander 2.4L 2AZ-FE Head Gasket and Head Bolt Thread Failure?

The 2001-2007 Highlander with the 2.4L 2AZ-FE 4-cylinder engine suffers from a design flaw where the aluminum head bolt threads strip out of the engine block. The plastic intake manifold traps heat against the block, causing thermal fatigue of the aluminum threads. This leads to… Repairs typically run $2,500-$5,000. Severity: high.

2006 Toyota Highlander Problems: 2 Issues Every Owner Should Know

All 2 Known Issues

2006-2013 Toyota Highlander: Hybrid Battery Pack Degradation and Failure#

Common Symptoms

How to Fix

What Owners Are Using

Research This Issue

2001-2007 Toyota Highlander: 2.4L 2AZ-FE Head Gasket and Head Bolt Thread Failure#

Common Symptoms

How to Fix

What Owners Are Using

Research This Issue

Other Toyota Models

Frequently Asked Questions

What are the most common Toyota Highlander problems?

Is the Toyota Highlander reliable?

How much does it cost to fix common Toyota Highlander problems?

What is the 2006-2013 Toyota Highlander Hybrid Battery Pack Degradation and Failure?

What is the 2001-2007 Toyota Highlander 2.4L 2AZ-FE Head Gasket and Head Bolt Thread Failure?