Some V-type engines use two catalytic converters in a row on each side, with a third oxygen sensor at the very end. When that last sensor on bank 2 has a circuit fault, the engine computer cannot check the final converter on that side. A P0162 code means the engine computer found a problem in the circuit of oxygen sensor 3 on bank 2.
This guide explains where this sensor sits, what it does and how to test its circuit.
P0162 Code Breakdown
Every OBD-II code follows the same five-character pattern set by the SAE J2012 standard. Each character narrows down which system has the fault. This table shows what each part of the code tells you.
| Character | Meaning | What It Tells You |
|---|---|---|
| P | Powertrain | The fault is in the engine or transmission systems. |
| 0 | Generic (SAE) code | The definition is the same on every OBD-II vehicle. |
| 1 | Fuel and air metering | The fault involves the sensors that measure air and fuel. |
| 62 | Specific fault | O2 Sensor Circuit Malfunction (Bank 2 Sensor 3) |
What the P0162 Code Means
The SAE J2012 standard defines the P0162 code as O2 Sensor Circuit Malfunction (Bank 2 Sensor 3). Bank 2 is the side of the engine without cylinder 1. Sensor numbers count back from the engine, so sensor 3 sits after the second catalytic converter on that side.
Only vehicles with two converters per bank use sensor 3. The first converter is often a small unit close to the engine that heats up quickly. The second is a larger one under the floor. Sensor 3 helps the powertrain control module (PCM) check how well that last converter works.
A healthy sensor 3 holds a fairly steady reading once everything is hot. This code sets when its signal or circuit does not behave as the PCM expects.
Signs of a Bank 2 Sensor 3 Fault
Sensor 3 plays almost no role in fuel control. Signs of a P0162 code include:
- Check engine light on
- Catalyst monitor that will not complete
- Failed emissions test
- Other bank 2 sensor 3 codes stored at the same time
Common Causes of the P0162 Code
This sensor sits far back under the vehicle, exposed to water, salt and debris. These are the usual causes:
- Damaged wiring. Long wire runs are easy to snag, chafe or melt.
- Corroded connector. Road spray attacks the pins.
- Failed oxygen sensor. Age and contamination wear out the element.
- Exhaust leak near the sensor. Rust holes let outside air reach it.
- Heater circuit fault. A cold sensor gives a weak or flat signal.
- Wrong replacement part. A sensor made for another position may not match.
How to Diagnose the P0162 Code
You need a scan tool with live data, a multimeter and the wiring diagram. Drive at least 15 minutes so both converters are hot.
Confirm the Sensor Position
Use your service manual to find bank 2 sensor 3. It is usually the last oxygen sensor on the bank 2 side, after the second converter. Mixing up sensor positions is a common and costly mistake.
Compare with Bank 1 Sensor 3
Graph both sensor 3 readings together. They should look similar, holding fairly steady while cruising, dropping low during a coast and rising when you accelerate. If bank 2 sensor 3 is stuck at 0 volts, above 1 volt or flat near 0.45 volt while bank 1 looks normal, the fault is on bank 2.
Inspect the Wiring and Exhaust
Follow the sensor wiring forward to its connector. Look for torn insulation, melted spots and missing clips. Check the exhaust around the sensor for holes, cracked joints and soot marks.
Repairs That Fix the P0162 Code
Match the repair to your results, then clear the code and drive until the monitors complete.
- Repair damaged wiring and secure it with clips away from the exhaust.
- Clean or replace the connector if the pins are corroded.
- Fix exhaust leaks near the sensor.
- Replace bank 2 sensor 3 with a part listed for that exact position.
After the repair, plan a mix of city and highway driving. The catalyst monitor often needs a steady cruise and several warm-ups before it runs. Check the monitor status with your scan tool before an emissions test.
Repair Cost Breakdown
The cost to fix a P0162 code is usually moderate. This table lists typical ranges.
| Repair | DIY Cost | Typical Shop Cost |
|---|---|---|
| Connector cleaning or pigtail | $10 to $40 | $75 to $200 |
| Wiring repair | $10 to $30 | $100 to $300 |
| Bank 2 sensor 3 replacement | $30 to $130 | $120 to $350 |
| Exhaust leak repair | $20 to $100 | $150 to $500 |
Is It Safe to Drive with a P0162 Code?
Yes, in most cases. The front sensors handle fuel control, so the engine runs as usual.
The PCM cannot fully check the last bank 2 converter, though, and the vehicle will fail an emissions test. Fix it before your next inspection.
Related Codes
These codes often show up with this one or point to the same system:
| Code | Meaning |
|---|---|
| P0160 | O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 2) |
| P0161 | O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2) |
| P0163 | O2 Sensor Circuit Low Voltage (Bank 2 Sensor 3) |
| P0164 | O2 Sensor Circuit High Voltage (Bank 2 Sensor 3) |
| P0165 | O2 Sensor Circuit Slow Response (Bank 2 Sensor 3) |
Getting Bank 2 Sensor 3 Working Again
A P0162 code means the PCM found a fault in the bank 2 sensor 3 circuit. Wiring damage, corroded connectors and worn sensors cause most cases.
- Confirm the sensor position in your service manual.
- Compare bank 2 sensor 3 with bank 1 sensor 3.
- Inspect the long wire run under the vehicle.
- Replace the sensor with a part made for that position.
Frequently Asked Questions
Which Vehicles Have Bank 2 Sensor 3?
Only V-type or flat engines with two catalytic converters in a row on each side have this sensor. You find it on some low-emission models, trucks and SUVs. If your vehicle sets this code, the service manual shows exactly where the sensor sits.
Does Sensor 3 Affect Engine Performance?
Very little. The front sensors control fuel, and the sensor 2 readings may add small corrections. Sensor 3 mainly monitors the last converter. A fault usually affects emissions testing rather than power or fuel economy.
Can I Use a Bank 1 Sensor 3 Part on Bank 2?
Sometimes, if the parts catalog lists the same number for both positions. Connector shape and wire length often differ from side to side, though. Order by the exact position so the connector reaches without stretching.
How Do I Reach Sensor 3 Safely?
Raise the vehicle on ramps or jack stands on level ground, never on a jack alone. Let the exhaust cool fully. Soak the sensor threads with penetrating oil, then use an oxygen sensor socket to remove it without damaging the wires.
What If Sensor 3 Codes Appear on Both Banks?
Matching codes on both banks point to something the two sensors share, such as a heater fuse, a ground or a wiring junction. Check those shared parts before buying two sensors. It is rare for both sensors to fail at exactly the same time.