P0153

P0153-O2 SENSOR 2/1 SLOW RESPONSE

For a complete wiring diagram consult Diagrams/Electrical.

- When Monitored:
With the engine running, vehicle speed between 32 and 88 kph (20 and 55 mph), throttle open for a minimum of 120 seconds, ECT greater than 70° C (158° F), Catalytic Converter Temperature greater than 600° C (1112° F) and EVAP Purge active

- Set Condition:
The PCM detects that the oxygen sensor signal switches from lean to rich less than 16 times within 20 seconds during monitoring. Two Trip Fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.

Diagnostic Test

1. DTC IS ACTIVE

NOTE: If an O2 sensor signal circuit is shorted to voltage, all O2 sensor voltage readings displayed on the scan tool will be approximately 5.0 volts. Diagnose the sensor that set the most current DTC.

NOTE: After repairs have been completed, verify proper O2 Sensor operation. If all O2 Sensor voltage readings have not returned to normal, perform the diagnostic procedure for the remaining O2 Sensors.

NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set.

Start the engine and allow it to reach operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

With a scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go to 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking For An Intermittent DTC

2. CHECKING THE EXHAUST SYSTEM FOR LEAKS
Perform the diagnostic procedure for *CHECKING THE EXHAUST SYSTEM FOR LEAKS. Checking the Exhaust System For Leaks
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Go to 3

3. (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO VOLTAGE

Turn the ignition off.
Disconnect the 2/1 Oxygen Sensor harness connector.
Disconnect the Powertrain Control Module (PCM) harness connector.
Turn the ignition on.
Measure the voltage of the (K43) O2 2/1 Signal circuit in the 2/1 Oxygen Sensor harness connector.

NOTE: Measure the voltage in reference to ground, not the (K902) O2 Return (Up) circuit.

Is there any voltage present?

Yes

- Repair the (K43) O2 2/1 Signal circuit for a short to voltage.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Go to 4

4. (K902) O2 RETURN (UP) CIRCUIT SHORTED TO VOLTAGE

Measure the voltage of the (K902) O2 Return (Up) circuit in the 2/1 Oxygen Sensor harness connector.
Is there any voltage present?

Yes

- Repair the (K902) O2 Return (Up) circuit for a short to voltage.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Go to 5

5. (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO GROUND

Turn the ignition off.
Measure the resistance between ground and the (K43) O2 2/1 Signal circuit in the 2/1 Oxygen Sensor harness connector.
Is the resistance below 100 ohms?

Yes

- Repair the (K43) O2 2/1 Signal circuit for a short to ground.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Go to 6

6. (K902) O2 RETURN (UP) CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (K902) O2 Return (Up) circuit in the 2/1 Oxygen Sensor harness connector.
Is the resistance below 100 ohms?

Yes

- Repair the (K902) O2 Return (Up) circuit for a short to ground.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Go to 7

7. (K43) O2 2/1 SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals, resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Measure the resistance of the (K902) O2 Return (Up) circuit between the 2/1 Oxygen Sensor harness connector and the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?

Yes

- Go to 9

No

- Repair the (K902) O2 Return (Up) circuit for an open circuit or high resistance.
- Perform the PCM Verification Test.Powertrain Verification Test

9. 2/1 OXYGEN SENSOR

NOTE: Check for signs of contaminants that may have damaged the O2 Sensor, such as contaminated fuel, unapproved silicone, oil and coolant.

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the 2/1 Oxygen Sensor and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Replace the 2/1 Oxygen Sensor.
- Perform the PCM Verification Test.Powertrain Verification Test