P0051 OLDSMOBILE - HO2S Heater Control Circuit Low Bank 2 Sensor 1
P0051 OLDSMOBILE Possible Causes
- Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1
- Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 harness is open shorted
- Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 circuit poor electrical connection
- Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 fuse
- Faulty Engine Control Module (ECM)
First diagnose P0051 OLDSMOBILE code
Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded terminals.
P0051 OLDSMOBILE Tech NotesThe code means that there is a problem with the heater element circuit of the heated oxygen sensor. Water getting inside the heated oxygen sensor connector can caused the heated oxygen sensor fuse to blow, which is a very common problem for this type codes. Before replacing the sensor, check for the condition of the heated oxygen sensor fuse and connectors.
Cost of diagnosing the P0051 OLDSMOBILE code
Labor: 1.0The cost of diagnosing the P0051 OLDSMOBILE code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
When is the P0051 OLDSMOBILE code detected?The P0051 is set when the ECM detects an excessively low voltage through the heated oxygen sensor heater circuit
P0051 OLDSMOBILE Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P0051 OLDSMOBILE MeaningThe Heated Oxygen (HO2S) bank 2 sensor 1 is threaded into the exhaust manifold. The sensor is equipped with a heater element to decrease the amount of time required to enter closed loop fuel control. The Engine Control Module (ECM) controls the heater by pulsing circuit 551 to ground. When the heater is commanded Off (circuit not grounded), the voltage level at the ECM should be high (ignition voltage). When the heater is commanded On (circuit grounded), the voltage level at the ECM should be low. The ECM heater feedback circuit uses a pull-up voltage (1.6-3.6 volts), which allows the ECM to individually differentiate between an open, short to ground or short to voltage.
P0051 OLDSMOBILE More InformationNeed more information on how to fix the P0051 OLDSMOBILE code?
Get Access to Factory Service Manuals