Fix it
- 2012 truck: ask for a 20TC01 VIN check
Toyota's campaign repairs or replaces the air injection pump and replaces the air switching valves free of charge on covered trucks built late August 2011 to early August 2012. The letter gives no end date.
- 2010–2014 with the 2.7L: ask about F0U
On covered trucks with the 2TR-FE engine, Toyota replaces the exhaust pipe with catalytic converters at no charge.
- 2024–2025 4WD with flashing 4WD lights: cite T-SB-0093-25
Toyota's repair is a new transfer case shift actuator and an updated breather hose, for trucks built before the VINs the bulletin lists.
- Any other year: get the code read and recorded
Owners outside 2012 report rodent-chewed wiring or hoses, misfires and a few secondary air faults. The code is what separates them.
- TRAC OFF without pressing the switch: see a dealer
The 2012, 2015 and 2018 Tacoma manuals say TRAC and hill-start assist control cannot be operated in that case, and to contact a Toyota dealer.
As an Amazon Associate, Toyota Readout earns from qualifying purchases — if a scan tool or part you buy through these links helps, it costs you nothing extra.
See the LAUNCH CRP123 on Amazon → With live data, a reader like the LAUNCH CRP123 turns a mystery light into a named code.What's going on
In owner complaints, TRAC OFF next to the check engine light on a Tacoma leads back to one model year more than any other. NHTSA holds 8,451 Tacoma complaints from 1995 to 2026. Among them, 226 mention the check engine light, and 90 of those 226 bring up TRAC, VSC or traction control as well. Of the 90, 62 are 2012 trucks, and on 54 of those 62 the owner names the secondary air injection system.
Toyota has paperwork for that fault: a service bulletin, a customer support program, and a special service campaign that repairs it free of charge on covered trucks. The 2012 story comes first, then the 2.7-liter campaign for 2010–2014, the 2024–2025 4WD bulletin and other years. Other Toyotas get their own treatment in the overview of TRAC OFF with the check engine light.
One caution on the numbers: NHTSA doesn’t check what owners write, and a pile of complaints is not a failure rate.
2012 Tacoma: the secondary air injection fault
Of the 62 complaints on 2012 trucks, 54 point to the secondary air injection system. They name a code in the P2440–P2445 or P2433–P2438 range, or P0412, or the air pump and switching valves themselves. One owner’s account is typical: “THE CHECK ENGINE LIGHT AND TRACTION CONTROL OFF LIGHT CAME ON AND TRUCK IMMEDIATELY WENT IN TO LIMP-HOME MODE … P2440 AND P2442” (ODI 11194082).
Limp mode is what owners stress. In 48 of the 54, the truck lost power or was held to a low speed or rpm. They put numbers on it: the truck “would not go over 25 MPH,” it hit a “2500 RPM limit,” or it “would only go about 35mph.”
The other 8 of the 62 differ: one dealer found a bad battery cell that had blown the IGN fuse, another found rodent-chewed knock sensor wiring, and 6 give no clear cause.
Before Toyota’s campaign, owners report quotes of $940 for a valve alone (ODI 10886218), $1,709 (ODI 10978966), around $2,000 to $2,100 in several cases, and $2,458.08 in Puerto Rico (ODI 11235367). Each is one owner’s figure, not a price guide.
What Toyota published for the 2012 truck
| Document | Date | What it does |
|---|---|---|
| Bulletin T-SB-0333-17 | Dec 12, 2017; Rev1 May 11, 2018 | Repair for P2440, P2442 and (Rev1) P2445 on 1GR-FE trucks |
| Program ZHA | Jan 11, 2018; updated Jul 26, 2018 | Covers check engine light repairs caused by moisture in the pumps or valves |
| Campaign 20TC01 | Dealer letter May 28, 2020 | Pump repaired or replaced, valves replaced, free of charge |
T-SB-0333-17 opens: “Some 2012 model year Tacoma vehicles equipped with the 1GR-FE engine may exhibit a MIL ‘ON’ condition with …” and lists P2440 (Secondary Air Injection System Switching Valve Stuck Open Bank 1) and P2442, the same fault on Bank 2. The revision adds P2445 (Secondary Air Injection System Pump Stuck Off). The original bulletin blames “moisture intrusion into the air injection pump”; Rev1 says “air injection pump filter damage.” The repair is a new air pump assembly and new air switching valves.
Program ZHA covers certain 2012 Tacomas built from late August 2011 to early August 2012, about 87,000 trucks. It covers check engine light repairs “due to moisture/water in the Air Injection Pumps and/or Air Switching Valves.” Primary coverage ran until February 28, 2019, followed by 10 years from the date of first use, regardless of mileage.
Special Service Campaign 20TC01 covers the same production window, about 78,900 trucks, under the heading Air Injection Pumps and Air Switching Valves. Toyota’s dealer letter says “moisture in the air may cause a filter in the vehicle emissions system to degrade … and illuminate the check engine light.” The dealer inspects the pump and either repairs it with an improved filter or replaces it, then replaces the air switching valves, “FREE OF CHARGE.”
The letter gives no end date, and Toyota mailed reminder postcards for 20TC01 as late as December 2022. Owners don’t all get the same answer, though. One 2012 owner who contacted Toyota in August 2022 reports being told “the Special Service Campaign: 20TC01 had expired” (ODI 11482001). Have a dealer run your VIN and get the answer in writing.
The campaign is written for 2012 trucks. A 2014 owner whose mechanic tied the failure to 20TC01 reports that “the contact was informed that the vehicle was not covered under the campaign” (ODI 11732492).
None of these three Toyota documents mentions TRAC OFF; that link comes from owners.
2010–2014 Tacoma with the 2.7-liter: campaign F0U
Trucks with the 2TR-FE engine, the 2.7-liter four-cylinder, have a campaign of their own. Toyota’s F0U dealer letter (November/December 2015) covers certain 2010–2014 Tacomas, about 170,200 of them: “the front catalytic converter internal components may become deteriorated and begin to rattle … could become dislodged and restrict the exhaust flow. If this occurs, the vehicle may illuminate a check engine light, and, depending on the level of exhaust restriction, the vehicle may experience a reduction in power.”
The remedy is a replacement exhaust pipe with catalytic converters, at no charge. Like 20TC01, the letter states no end date, so check the VIN. It mentions the check engine light and power loss, and says nothing about TRAC OFF.
2024–2025 4WD Tacoma: flashing 4WD lights
Toyota’s bulletin T-SB-0093-25 (December 17, 2025) covers some 2024–2025 4WD Tacoma and Tacoma Hybrid models where “4WD lights are flashing and a MIL ON condition” shows up. The codes are P277111 (4WD Low Switch Circuit Short to Ground) plus P178462 and P17AC62, which the bulletin groups as transfer case shift motor limit switch signal compare failures.
Toyota updated the transfer case breather hose; the repair is a new transfer case shift actuator plus the new hose, for trucks built before the VINs the bulletin lists. The bulletin is about 4WD lights and the check engine light, not TRAC OFF, but if that is what your new Tacoma shows, take the number to the dealer.
Other model years
Outside 2012, only 28 complaints mention both lights, and they’re spread thin:
| What the owner reports | Complaints | ODI numbers |
|---|---|---|
| Secondary air injection | 3 | 11092039 (2013), 11732492 (2014), 11515122 (2015) |
| Rodent-chewed wiring or hoses | 4, plus 1 on a 2012 | 10821880, 10811312, 10661583, 11079194; 10721365 (2012) |
| Misfire or cylinder fault | 5 | 11153649, 11741962, 11444211, 11302999, 11562245 |
| Other or unclear | 16 | Not listed |
The 2013 owner reports P2437 and P2438 with limp mode, and the 2015 owner P0418. The rodent cases stand out on a truck. One 2014 owner says the dealer’s technician told them that “RODENTS ATE THE HOSE CONNECTING FUEL INJECTOR AIR PUMP TO VALVE WHICH TRIGGERS THE ECU TO FAULT AND CASCADES FAILURE TO STABILITY CONTROL” (ODI 10661583). That is a technician’s explanation passed along by an owner, not something Toyota has published.
Recall 20V-012 also lists certain 2018–2019 Tacomas. Its subject is the low-pressure fuel pump, and the engine can stall if it fails, so check the recall against your VIN if you drive one of those years.
What the Tacoma manuals say, and what they don’t
Toyota’s owner’s manuals don’t explain why an engine fault and TRAC OFF arrive together. The 2012, 2015 and 2018 Tacoma manuals were part of our search, along with 160 Toyota bulletins for the Tacoma, Corolla and RAV4, read in full text, whose summaries name the check engine light or a trouble code. None gives a reason, and no bulletin mentions TRAC OFF or VSC. Nineteen of the bulletins were scanned images with no searchable text.
What the manuals do cover is a TRAC OFF light you didn’t cause. The 2012 manual (page 204) and the 2015 manual (page 194) describe the TRAC OFF indicator coming on even though the VSC OFF switch has not been pressed, and conclude: “TRAC, hill-start assist control, downhill assist control system cannot be operated. Contact your Toyota dealer.” The 2018 manual (page 321) lists fewer systems: ”…TRAC and hill-start assist control cannot be operated. Contact your Toyota dealer.”
So on these trucks, an unexplained TRAC OFF light covers more than traction control. Hill-start assist goes with it, and on the 2012 and 2015 trucks, downhill assist control too. The owner data supplies the cause named most often on a 2012: the secondary air injection system, with most of those owners describing limp mode.
The switch: 2WD and 4WD work differently
The 2012 Tacoma manual gives the switch different jobs depending on the drive mode. On 2WD models, and on 4WD trucks in 2WD mode, the only option is press and hold for more than 3 seconds with the vehicle stopped. That turns off TRAC, VSC and Trailer Sway Control together (page 202). In 4WD mode the switch also takes a quick press, which turns off TRAC alone (page 203).
The manual pictures the switch instead of giving its location. When TRAC OFF stays lit after you’ve used it, see the TRAC OFF light that won’t turn off; with VSC OFF lit as well, the TRAC OFF and VSC light guide covers the pair.
A blinking check engine light, and clearing it
Under California’s OBD II regulation, a check engine light blinking once per second marks a misfire in progress, right now, at a level that can damage the catalytic converter. Vehicles that shut off fuel during that kind of misfire are allowed to keep the light steady instead. Five of the Tacoma complaints outside 2012 name a misfire or cylinder fault; what to do about a blinking light is on our flashing check engine light page.
Toyota’s clearing guidance on this page comes from another model: the 2023 Camry owner’s manual is the only one we read on it. With a loose fuel cap, it says to tighten it, and “The light will go off after several driving trips. If the light does not go off even after several trips, contact your Toyota dealer as soon as possible” (page 533). It adds that the cap’s “error code in the OBD system will not be cleared unless the vehicle is driven 40 or more times” (page 454). Our reset guide picks up from there, and the Tacoma check engine light page covers the truck’s codes beyond this pair.