For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptor

DTC P253F: Engine Oil Life

### Circuit/System Description

The engine control module calculates engine oil life based on engine speed and temperature. Based on driving conditions, the mileage at which an oil change will be indicated can vary considerably. For the oil life system to work properly, you must reset the system every time the oil is changed.

### Conditions for Running the DTC

• | The ignition is ON.

• | The DTC runs continuously once the above condition is met.

### Conditions for Setting the DTC

The engine control module (ECM) detects the engine oil needs to be changed soon.

### Action Taken When the DTC Sets

DTC P253F is a Type C DTC.

### Conditions for Clearing the DTC

DTC P253F is a Type C DTC.

### Circuit/System Verification

DTC P253F is an informational DTC. Change the engine oil, and reset the oil life monitor.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Engine Oil and Oil Filter Replacement

### Repair Verification

Ignition ON, observe the scan tool DPF soot mass parameter. The parameter should be less than 24 grams.

⇒ | If greater than the specified range, perform a DPF service regeneration. Refer to Exhaust Particulate Filter Cleaning .