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 P0443 00: Evaporative Emission (EVAP) Purge Solenoid Valve Control Circuit
DTC P0458 00: Evaporative Emission (EVAP) Purge Solenoid Valve Control Circuit Low Voltage
DTC P0459 00: Evaporative Emission (EVAP) Purge Solenoid Valve Control Circuit High Voltage

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Ignition 1 Voltage - Purge Supply | P0443 00, P0458 00 | P0443 00, P0458 00 | -- | --
EVAP Purge Solenoid Control | P0443 00, P0458 00 | P0443 00, P0458 00 | P0459 00 | --

### Circuit/System Description

An ignition voltage is supplied directly to the EVAP canister purge solenoid valve. The engine control module (ECM) grounds the EVAP canister purge solenoid valve control circuit through an internal switch called a driver. The ECM monitors the status of the driver. The EVAP canister purge solenoid valve is pulse width modulated (PWM). A scan tool will display the amount of ON time as a percentage.

### Conditions for Running the DTC

• | Engine is running.

• | DTCs P0606 00, P0628 00, or P0629 00 are not set.

• | The battery voltage is greater than 9 V.

### Conditions for Setting the DTC

#### P0458 00

PWM signal is less than 99%

#### P0459 00

PWM signal is greater than 0.3%

### Action Taken When the DTC Sets

DTCs P0443 00, P0458 00 and P0459 00 are Type B DTCs.

### Conditions for Clearing the DTC

DTCs P0443 00, P0458 00 and P0459 00 are Type B DTCs.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Evaporative Emission Control System Description

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the Q12 Evaporative Emission (EVAP) Canister Purge Solenoid Valve.
2. Ignition ON, verify that a test lamp illuminates between the voltage supply circuit terminal 1 and ground.

⇒ | If the test lamp does not illuminate, test the voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the voltage supply circuit fuse is open, test or replace the Q12 Evaporative Emission (EVAP) Canister Purge Solenoid Valve.

3. Ignition OFF, test for more than 500 kΩ between the control circuit terminal 2 and ground.

⇒ | If less than the specified range, repair the short to ground. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

4. Ignition OFF, test for less than 0.3 V between the control circuit terminal 2 and ground.

⇒ | If more than the specified range, repair the short to B+. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

5. Ignition OFF, disconnect the K20 Engine Control Module (ECM). Test for less than 5 Ω between the Q12 Evaporative Emission (EVAP) Canister Purge Solenoid Valve connector terminal 2 and the K20 Engine Control Module (ECM) terminal 29 (X1).

⇒ | If more than the specified range, repair the open circuit. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

### Component Testing

#### Static Test

Ignition OFF, disconnect the harness connector at the solenoid. measure for 10-30 Ω between the voltage supply terminal 1 and the control circuit terminal 2.

⇒ | If not within the specified range, replace the Q12 Evaporative Emission (EVAP) Canister Purge Solenoid Valve.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Refer to LINK EVAP PURGE AND VENT Replacement

• | Engine Control Module Replacement for ECM replacement, setup, and programming