B : REPLACE ECM (See REMOVAL )
A : END
DTC P2237 OXYGEN (A/F) SENSOR PUMPING CURRENT CIRCUIT/OPEN (BANK 1 SENSOR 1);
DTC P2238 OXYGEN (A/F) SENSOR PUMPING CURRENT CIRCUIT LOW (BANK 1 SENSOR 1);
DTC P2239 OXYGEN (A/F) SENSOR PUMPING CURRENT CIRCUIT HIGH (BANK 1 SENSOR 1);
DTC P2240 OXYGEN (A/F) SENSOR PUMPING CURRENT CIRCUIT/OPEN (BANK 2 SENSOR 1);
DTC P2241 OXYGEN (A/F) SENSOR PUMPING CURRENT CIRCUIT LOW (BANK 2 SENSOR 1);
DTC P2242 OXYGEN (A/F) SENSOR PUMPING CURRENT CIRCUIT HIGH (BANK 2 SENSOR 1);
DTC P2252 OXYGEN (A/F) SENSOR REFERENCE GROUND CIRCUIT LOW (BANK 1 SENSOR 1);
DTC P2253 OXYGEN (A/F) SENSOR REFERENCE GROUND CIRCUIT HIGH (BANK 1 SENSOR 1);
DTC P2255 OXYGEN (A/F) SENSOR REFERENCE GROUND CIRCUIT LOW (BANK 2 SENSOR 1);
DTC P2256 OXYGEN (A/F) SENSOR REFERENCE GROUND CIRCUIT HIGH (BANK 2 SENSOR 1)
DESCRIPTION
HINT:
Although the DTC titles say oxygen sensor, these DTCs relate to the Air-Fuel Ratio (A/F) sensor.
Sensor 1 refers to the sensor mounted in front of the Three-Way Catalytic Converter (TWC) and located
near the engine assembly.
The A/F sensor, which is located between the exhaust manifold and catalyst, consists of alloyed metal elements
and a heater.
Depending on the engine operating conditions, the heater heats the sensor elements to activate them. Battery
voltage is applied to the heater, the sensor ground is controlled by the ECM using a duty ratio. The sensor
elements convert the oxygen concentration in the exhaust gas into voltage values to output. Based on the
voltage, the ECM determines the air-fuel ratio and regulates the fuel injection volume depending on the air-fuel
ratio and engine operating conditions. The voltage changes between 0.6 V and 4.5 V while the engine is
running. If the air-fuel ratio is lean, which means the oxygen concentration in the exhaust gas is high, the
voltage is high. If the air-fuel ratio is rich, which means the oxygen concentration in the exhaust gas is low, the
voltage is low.
P2195, P2196, P2197 or P2198 (A/F sensor pending DTCs)
B
2008 Toyota Tundra
2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra