P0059
UniversalHO2S Heater Resistance (Bank 2, Sensor 1)
Medium SeverityThe P0059 code indicates an issue with the heater circuit's resistance in the Bank 2, Sensor 1 oxygen sensor. This means the engine's computer isn't detecting the correct electrical resistance needed to warm up the sensor, which can lead to decreased fuel efficiency and increased emissions as the sensor won't reach operating temperature quickly enough.
⚠️ Before You Begin (Safety First)
Always wear appropriate personal protective equipment, including gloves and eye protection. Ensure the engine is cool before working on exhaust components. Disconnect the battery's negative terminal before performing any electrical diagnostics or repairs to prevent accidental shorts or shocks. Be aware that exhaust components can remain hot for a long time after the engine is turned off.
Common Symptoms
- Check Engine Light illumination
- Reduced fuel economy
- Increased vehicle emissions
- Rough idling (less common)
- Engine hesitation (less common)
Common Causes
- Faulty Bank 2, Sensor 1 oxygen sensor (heater element failure)
- Damaged or corroded wiring to the oxygen sensor heater circuit
- Blown fuse for the oxygen sensor heater circuit
- Poor connection at the oxygen sensor electrical connector
- Faulty Engine Control Module (ECM) (rare)
Frequently reported on: Ford F-150 (2004-2014), Chevrolet Silverado 1500 (2003-2013), Toyota Tundra (2007-2015), Dodge Ram 1500 (2006-2012)
Diagnostic Steps
- Use an OBD-II scanner to confirm P0059 is the only code present. Clear codes and see if it returns.
- Visually inspect the wiring harness and electrical connector for the Bank 2, Sensor 1 oxygen sensor for any signs of damage, fraying, corrosion, or loose connections. Repair as needed.
- Locate and check the fuse(s) related to the oxygen sensor heater circuit (refer to your vehicle's service manual). Replace any blown fuses.
- If accessible, use a multimeter to check the resistance of the heater circuit on the oxygen sensor itself (refer to factory specifications for correct values).
- If the sensor's heater resistance is out of specification, replace the Bank 2, Sensor 1 oxygen sensor.
- After replacement, clear the fault code and perform a test drive to ensure the repair is successful and the code does not return.
👨🔧 When to Call a Professional
If you have replaced the oxygen sensor and the code persists, or if you find extensive wiring damage, it's best to consult a professional mechanic. Diagnosing intermittent electrical issues or an internal ECM fault can be complex and requires specialized tools and expertise.
Commonly Asked Questions
What does 'Bank 2, Sensor 1' mean?
Bank 2 refers to the cylinder bank that does not contain cylinder #1. Sensor 1 refers to the oxygen sensor located before the catalytic converter (upstream sensor) for that bank. These sensors measure oxygen content in the exhaust before it enters the converter.
Can I drive my car with a P0059 code?
While you can drive with a P0059 code, it's not recommended for extended periods. Your vehicle's fuel economy will likely be reduced, and emissions will increase. Long-term driving with this code can also potentially lead to premature failure of your catalytic converter.
How can I test the oxygen sensor heater circuit?
You can test the heater circuit using a multimeter. With the sensor disconnected, measure the resistance between the two heater wires (usually the same color). Compare the reading to your vehicle's factory specifications. You can also check for voltage supply to the heater circuit connector from the vehicle harness side.
What if I replace the sensor, and P0059 comes back?
If the code returns after replacing the oxygen sensor, the issue is likely not the sensor itself. You'll need to thoroughly re-inspect the wiring harness for damage or corrosion, check relevant fuses, and ensure proper voltage supply to the heater circuit. In rare cases, the Engine Control Module (ECM) could be faulty.
Is a P0059 code an expensive repair?
The cost of repair is usually moderate. The primary component to replace is the oxygen sensor, which varies in price. Labor costs would depend on the sensor's accessibility. If the issue is wiring or a fuse, the repair could be much less expensive.