OBD-II trouble code
P0435: Catalyst Temperature Sensor (Bank 2)
The module has lost a usable signal from the catalyst temperature sensor on bank 2. Identify that bank from the cylinder diagram before the sensor is ordered. Access follows that diagram, not a rule about which bank is buried.
Quick facts
- System
- Powertrain
- Category
- Emissions / Catalyst
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $120 – $800
- DIY difficulty
- Intermediate DIY
Browse every code in P0400–P0499, or start from the full code library.
What does P0435 mean?
This is the bare circuit code for the bank 2 catalyst temperature probe. It sets when the signal is not merely questionable but unusable — reading as open, shorted, or parked at a value that could not correspond to any temperature a real exhaust has ever been. The module has not concluded that anything is wrong with the converter. It has concluded that it can no longer see the converter's temperature.
Bank 2 is the bank that does not contain cylinder 1, and the diagram is the only map. On a longitudinal GM LS truck with cylinder 1 on the driver side, bank 2 is the passenger side. Summit's Gen 3 Hemi numbering puts cylinders 1, 3, 5, and 7 on the driver side, so bank 2 is the other side. Summit's Ford Modular numbering puts cylinders 1 through 4 on the passenger side, so bank 2 is the driver side. Honda's bulletin for the listed Pilot, Ridgeline, and Odyssey calls bank 1 the rear bank, which puts bank 2 at the front on those vehicles. Toyota GR and Nissan VQ numbering is not taken from that Honda bulletin. Each of those engines comes from its own diagram.
Once the diagram names the bank, access is whatever that side of this engine requires. A longitudinal layout and a transverse layout are not the same job, and neither one has a published labor time on this page. A quote is checked against the labor operation for this VIN.
Confirm thermistor or thermocouple from the diagram before an ohm test. A thermistor is checked against the resistance the chart lists at a stated temperature. A thermocouple is not condemned with that ohm test. The lead runs along the exhaust, so inspect it only after the pipe is cool. Chafe, a corroded connector, a cracked tip, and seized threads are what that inspection is looking for. They are not ranked.
Swap the two sensors only when the parts listing shows the same part number, and only after the exhaust is cool. If the fault moves with the sensor, the sensor failed the swap. If P0435 stays on bank 2, the harness, the connector, or the module input is next. Do not swap across mismatched part numbers.
Common causes
- Sensor lead chafed through where it runs against the bank 2 exhaust pipe or a heat shield
- Corroded, wet or heat-damaged connector at the bank 2 sensor
- Sensor element failed open internally after years of thermal cycling, or a cracked tip
- Short to ground through damaged insulation, with the exhaust acting as the return path
- Connector left unlatched or a terminal backed out after previous work on bank 2
- Harness damaged during intake manifold, spark plug, manifold gasket or converter work on bank 2
- Open in the signal or ground circuit on the run the diagram shows back to the module
- Module input circuit failure, which the chart reaches only after the sensor and the wiring test normal
Symptoms
- Check engine light with P0435 stored
- Bank 2 catalyst temperature displayed as a fixed extreme value, or as no value at all
- Bank 1 temperature reading normally on the same scan tool screen, which is itself a clue
- Emissions monitors not completing, so the vehicle cannot be presented for a test
- Little or no difference in how the vehicle drives
- Loss of the module's converter overheat protection on that bank
Diagnostic steps
- 1.Confirm which physical bank is bank 2 on this specific engine before touching anything. It is the bank without cylinder 1, and the numbering convention varies by manufacturer.
- 2.Confirm the vehicle actually has a physical sensor there. Some vehicles display a modeled catalyst temperature calculated from load and airflow, in which case there is nothing in the exhaust to unplug.
- 3.Compare the live bank 1 and bank 2 catalyst temperature values with the engine cold. Bank 1 sitting near ambient while bank 2 sits at an extreme is a circuit fault, not a temperature difference.
- 4.Inspect the visible length of the bank 2 sensor lead, with the exhaust cool, before electrical testing. Chafe is inspected because the lead lies on the pipe. It is not ranked ahead of the connector.
- 5.Unplug the connector and examine both halves for corrosion, moisture, spread terminals and melted plastic.
- 6.Check which type of sensor this is first. A thermistor presents a resistance the specification gives at a stated temperature; a thermocouple generates a voltage and reads near zero ohms when healthy, so an ohm check on one would condemn a good part. On a resistive type, measure at ambient and compare against specification, or against the bank 1 sensor measured the same way — the second sensor is a free reference.
- 7.Let the exhaust cool fully, then swap the two sensors side to side and clear the codes. Confirm the part numbers match first, wear gloves, and expect seized threads on an older exhaust. If the fault follows the sensor to bank 1, the part is confirmed; if it stays on bank 2, the wiring or the module input is at fault.
- 8.With the sensor unplugged, check the harness for continuity and for shorts to ground back to the module, giving particular attention to any point where the bank 2 run crosses the engine.
- 9.Do not condemn the converter on this code. Confirm or exclude P0430 separately before exhaust parts are quoted.
Repair cost
$120 – $800
Read the printed bracket as a planning span, not a quoted price. The low end names the sensor or a connector repair after the circuit test has failed that part. The high end names the same repair when access on this bank is the labor operation, including a bung that will not release the sensor. This code is not a converter replacement unless a catalyst efficiency code is also stored and diagnosed.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with exhaust gas temperature sensor replacement preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
This is an intermediate DIY job. It usually involves diagnostic steps, specialty parts, and some careful work in tight spaces. If you have the tools and a service manual or trustworthy video for your specific vehicle, it is achievable in a weekend. Otherwise, a competent independent shop will be faster.