P0158 on Toyota: How to Diagnose & Fix
O2 Sensor Circuit High Voltage (Bank 2, Sensor 2)
2 Toyota models · 2 documented issues · $220-$600 repair
P0158 on Toyota by model: symptoms, diagnosis and fix
Toyota T-SB-0001-10 Rev1 covers specified 2007-2009 Camry VDS BK46K and 2010 VDS BK3EK applications. P0138/P0158 may result from incorrect air-fuel-sensor response, and P0606 may also be present due to incorrect downstream O2-sensor operation. Toyota distinguishes these paths using the complete DTC set, freeze-frame air-fuel/O2 voltage and downstream O2 impedance, followed by circuit inspection. It does not describe every P0606 as a sensor fault or support the original 2AZ-FE, 2006-2012, VSC/TRAC or battery claims.
Common Symptoms
- Malfunction indicator lamp with a covered combination of P0138, P0158 and/or P0606
How to Fix
Confirm the covered VDS/2GR-FE application and capture all DTCs plus freeze-frame data. Follow T-SB-0001-10 Rev1: use the specified air-fuel/O2 freeze-frame gates for P0138/P0158, and for a qualifying P0606 path verify O2 Sensor 2 voltage above 1.10 V and/or impedance above 300 ohms at normal operating temperature, then inspect the circuit for open, short or high resistance. Replace only the bulletin-identified sensor when every gate is met; otherwise continue repair-manual P0606 diagnosis. Do not buy the prior sensor from this card.
Owner tips & cautions
- TipSave the complete DTC set and freeze-frame air-fuel/O2 values before clearing codes; the bulletin's path depends on the combination and measured data.
- WarningDo not treat a standalone P0606 or a non-covered VDS/engine as an oxygen-sensor diagnosis. Follow the applicable repair manual instead.
Sources for this issue (1)
Second-generation Highlanders with the 2GR-FE V6 commonly set a check engine light for an upstream air/fuel ratio sensor whose signal sticks on the lean side of its range. The characteristic Toyota pattern is a downstream oxygen sensor circuit-high code (P0138 bank 1 or P0158 bank 2) appearing together with, or instead of, the A/F sensor code (P2195 bank 1, P2197 bank 2) — the ECM flags the rear sensor because the front sensor's slow response drives the fuel trim, so shops that replace the downstream O2 sensor first fix nothing. Toyota published a service bulletin covering 2008-2010 Highlander for exactly this combination, attributing it to incorrect air/fuel ratio sensor response. Symptoms are mild — a light, slightly worse fuel economy, occasional rough idle — but the car will fail emissions testing.
Common Symptoms
- Check engine light on
- Slightly reduced fuel economy
- Occasional rough or hunting idle
- Fails state emissions test
- Downstream O2 code returns after replacing the rear sensor
How to Fix
Check the A/F sensor harness for opens, shorts and chafing first; if the wiring is sound, replace the affected bank's upstream air/fuel ratio sensor. Use a genuine Denso/Toyota sensor — aftermarket A/F sensors are a repeat-failure source on this engine. Anti-seize sparingly on the threads only, never on the sensor tip. Bank 1 is the front (radiator-side) bank on the transverse 2GR-FE; bank 2 is the firewall side and is the harder of the two to reach. This is not covered by any recall.
Sources for this issue (3)
P0158 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0158 mean on a Toyota?
P0158 stands for "O2 Sensor Circuit High Voltage (Bank 2, Sensor 2)." The PCM detects a persistently high voltage from the Bank 2, Sensor 2 downstream O2 sensor, indicating a short to voltage, contamination, or a rich condition at the post-catalyst sensor. On Toyota it is documented across 2 models: Camry, Highlander.
What are the most common causes of P0158?
The most common causes of P0158 are: Faulty Bank 2 downstream O2 sensor, Short to voltage in signal wire, Coolant/contaminant on sensor, Rich exhaust condition, Wiring/connector fault. The specific cause varies by vehicle.
How much does it cost to fix P0158 on a Toyota?
Published repair estimates on Toyota range from $220 to $600 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0158 on a different make?
View P0158 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.