P0135 Code - O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
Quick Answer
Heated Oxygen Sensors (HO2S) are used for fuel control and post catalyst monitoring. Common causes include Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1, Heated Oxygen Sensor Bank 1 Sensor 1 harness is open shorted, Heated Oxygen Sensor Bank 1 Sensor 1 circuit poor electrical connection. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
- What it means
- P0135 indicates O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1.
- Common causes
- Common causes include Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1, Heated Oxygen Sensor Bank 1 Sensor 1 harness is open shorted, Heated Oxygen Sensor Bank 1 Sensor 1 circuit poor electrical connection.
- Severity
- Moderate - service should be scheduled soon.
- Can I drive?
- The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
Code P0135 Description
The Diagnostic Trouble Code (DTC) will be set when the ECM detects that the HO2S 1 heater current is out of factory specifications.
What are the Possible Causes of the DTC P0135?
- Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1
- Heated Oxygen Sensor Bank 1 Sensor 1 harness is open shorted
- Heated Oxygen Sensor Bank 1 Sensor 1 circuit poor electrical connection
- Heated Oxygen Sensor Bank 1 Sensor 1 circuit fuse
- Faulty Engine Control Module (ECM)
How to Fix the DTC P0135?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
User Submitted Video
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0135 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- P0135 Acura — Air/Fuel Ratio Sensor 1 Heater Circuit Malfunction
- P0135 Audi — HO2S11 Sensor Heater Circuit
- P0135 BMW — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Buick — HO2S Heater Performance Bank 1 Sensor 1
- P0135 Cadillac — HO2S Heater Performance Bank 1 Sensor 1
- P0135 Chevrolet — HO2S Heater Performance Bank 1 Sensor 1
- P0135 Chrysler — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Dodge — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Ford — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 GMC — HO2S Heater Performance Bank 1 Sensor 1
- P0135 Honda — Air/Fuel Ratio Sensor 1 Heater Circuit Malfunction
- P0135 Hummer — HO2S Heater Performance Bank 1 Sensor 1
- P0135 Hyundai — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Infiniti — HO2S11 Heater Circuit Fault
- P0135 Isuzu — HO2S Heater Performance Sensor 1
- P0135 Jeep — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 KIA — HO2S11 Heater Circuit
- P0135 Lexus — Heated Oxygen Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Lincoln — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Mazda — HO2S Heater Circuit Fault
- P0135 Mercedes-Benz — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Mercury — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 MINI — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Mitsubishi — HO2S11 Heater Performance
- P0135 Nissan — HO2S11 Heater Circuit Fault
- P0135 Pontiac — HO2S Heater Performance Bank 1 Sensor 1
- P0135 Saturn — HO2S Heater Performance Bank 1 Sensor 1
- P0135 Scion — Heated Oxygen Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Suzuki — O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Toyota — Heated Oxygen Sensor Heater Circuit Malfunction Bank 1 Sensor 1
- P0135 Volkswagen — HO2S11 Sensor Heater Circuit
Frequently Asked Questions about P0135 Code
1. What does code P0135 mean?
Code P0135 indicates a malfunction in the oxygen (O2) sensor heater circuit for Bank 1 Sensor 1, which is responsible for heating the sensor to ensure accurate readings.
2. What are the symptoms of a P0135 code?
Common symptoms include an illuminated check engine light, decreased fuel efficiency, rough idling, and increased emissions.
3. What causes the P0135 code to appear?
The most common causes are a faulty O2 sensor, damaged wiring or connectors, a blown fuse, or a failing engine control module (ECM).
4. How do I diagnose the P0135 code?
Diagnose by inspecting the O2 sensor, checking the heater circuit’s wiring and connectors, testing for proper voltage, and verifying fuse integrity.
5. Can I drive with a P0135 code?
While the vehicle may still drive, ignoring the code can lead to poor fuel efficiency, higher emissions, and potential damage to other components.
6. How is a P0135 code fixed?
Repairs typically involve replacing the faulty O2 sensor, repairing damaged wiring, replacing a blown fuse, or addressing ECM-related issues.
7. How much does it cost to fix a P0135 code?
Repair costs vary but typically range from $150 to $400, depending on whether the sensor or wiring needs replacement.
8. What tools are needed to fix a P0135 code?
You’ll need an OBDII scanner, a multimeter, and potentially a wrench or socket set to replace the O2 sensor.
9. Can a bad O2 sensor cause other codes to appear?
Yes, a faulty O2 sensor can trigger additional codes related to fuel mixture, emissions, or catalytic converter efficiency.
10. What is Bank 1 Sensor 1?
Bank 1 Sensor 1 refers to the oxygen sensor located upstream (before the catalytic converter) on the side of the engine with cylinder 1.
Discuss the causes and fixes for P0135 OBDII Code
-
I have a 2003 Toyota Avalon with about 35,000 miles on it. Recently, 3 lights went on: service engine soon (NOT flashing), VSC and TRAC. My trusted mechanic says that is caused by a bad oxygen sensor (P0135 B1, S1, HTR) that is seized in the exhaust manifold. His estimate to fix is quite expensive ($600 to $800) but he seems to think that the worst thing that could happen if not repaired is poor gas mileage.
My concern by not fixing it is potential long term engine damage and damage to the catalytic converter. Who is more correct???
Thank you very much for your feedback. -
Both are correct.
$600 to $800 It's probably too high, but I do agree that a bad O2 will cause poor gas mileage.
Poor reading from the O2 sensor may cause the engine to run too rich (too much gas) which may eventually damage the catalytic converter.
In short term a bad O2 sensor will only cause poor gas mileage, but in a long term it may damage the catalytic converter.
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