P2252

DTC P2252 Oxygen Sensor Pumping Ground Circuit Low (for A/F sensor) (Bank 1 Sensor 1)

HINT: Although the title (DTC description) says "oxygen sensor", this DTC is related to the "A/F sensor".

DTC Detection Condition:

CIRCUIT DESCRIPTION

MONITOR DESCRIPTION

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

The air-fuel ratio (A/F) sensor varies its voltage output in proportion to the air-fuel ratio. If impedance (alternating current resistance) or voltage output of the sensor deviates greatly from the standard, the ECM determines if an open or short malfunction is in the A/F sensor circuit.

Wiring Diagram:

Step 1:

Step 2 - 3:

INSPECTION PROCEDURE

HINT:
Hand-held tester only:
It is possible the malfunctioning area can be found using the ACTIVE TEST A/F CONTROL operation. The A/F CONTROL operation can determine if the A/F sensor, heated oxygen sensor or other potential trouble areas are malfunctioning or not.

a. Perform the ACTIVE TEST A/F CONTROL operation.

HINT: The A/F CONTROL operation lowers the injection volume 12.5% or increases the injection volume 25%.

1. Connect the hand-held tester to the DLC3 on the vehicle.
2. Turn the ignition switch ON.
3. Warm up the engine by running the engine at 2,500 rpm for approximately 90 seconds.
4. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/F CONTROL.
5. Perform the A/F CONTROL operation with the engine idle (press the right or left button).

Result:
A/F sensor reacts in accordance with increase and decrease of injection volume:
+25 % --> Rich output: less than 3.0 V
-12.5 % --> Lean output: more than 3.35 V
Heated oxygen sensor reacts in accordance with increase and decrease of injection volume:
+25 % --> Rich output: more than 0.55 V
-12.5 % --> Lean output: less than 0.4 V

NOTE: The A/F sensor output has a few seconds of delay and the heated oxygen sensor output has about 20 seconds of delay.

The following A/F CONTROL procedure enables a technician to check and graph the voltage outputs of both the A/F sensor and the heated oxygen sensor.




For displaying the graph, enter "ACTIVE TEST / A/F CONTROL / USER DATA", select "AFS B1S1 and O2S B1S2" by pressing "YES" and push "ENTER". Then press "F4".

HINT:
- If DTC P2238, P2239, P2252 or P2253 is displayed, check the bank 1 sensor 1 circuit.
- Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.