GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 1999 🢒 Grand Prix 🢒 DTC 🢒 DTC P0443 Evaporative Emission (EVAP) Purge Solenoid Control Circuit

Refer to

Cell 21: Engine Data Sensos-MAF, EVAP Vent, EVAP Purge, EGR


Object Number: 352441 Size: FS
Cell 11: IGN1-UH Fuse
Cell 10: Underhood Accessory Wiring Junction Block
Cell 10: IGN MAIN 1 MaxiFuse 40 A
Cell 21: Engine Data Sensors-Indicator Lamps
Cell 21: Engine Data Sensors-VSS, Cruise
OBDII Symbol Description Notice
Cell 14: Engine Grounds G100, G111 and G113
Cell 14: Engine Grounds G100, G111 and G113
Handling Electrostatic Discharge Sensitive Parts Notice

Circuit Description

Output Driver Modules (ODMs) are used by the PCM to turn on many of the current-driven devices that are needed to control various engine and Transmission functions. Each ODM is capable of controlling up to 7 separate outputs by applying ground to the device which the PCM is commanding ON. Unlike the Quad Driver Modules (QDMs) used in prior model years, ODMs have the capability of diagnosing each output circuit individually. DTC P0443 set indicates an improper voltage level has been detected on the output circuit which controls the EVAP Canister Purge Solenoid Valve.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC
    • An improper voltage level has been detected on the output circuit which controls the EVAP Canister Purge Solenoid Valve.
    • The above conditions are present for at least 30 seconds.

Action Taken When the DTC Sets
    • The PCM will illuminate the MIL during the second consecutive trip in which the diagnostic test has been run and failed.
    • The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.

Conditions for Clearing the MIL/DTC
    • The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
    • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
    • The DTC can be cleared by using the scan tool Clear Information function or by disconnecting the PCM battery feed.

Diagnostic Aids

Check for the following conditions:

    • Poor connection at the PCM.
        Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
    • Damaged harness.
    • Inspect the wiring harness for damage. If the harness appears to be OK, disconnect the PCM, turn the ignition ON and observe a voltmeter connected between the solenoid control circuit and ground at the PCM harness connector while moving connectors and wiring harnesses related to the solenoid. A change in voltage will indicate the location of the malfunction.

Review the Fail Records vehicle mileage since the diagnostic test last failed. This may help determine how often the condition that caused the DTC to be set occurs.

Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

  1. Normally, ignition feed voltage should be present on the control circuit with the PCM disconnected and the ignition turned ON.

    2.

  2. Checks for a shorted component or a short to B+ on the control circuit. Either condition would result in a measured current of over 500 milliamps. Also checks for a component that is going open while being operated, resulting in a measured current of 0 milliamps.

    3.

  3. Checks for a short to voltage on the control circuit.

    4.

  4. This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.

DTC P0443-- EVAP Canister Purge valve Control CKT

Step

Action

Value(s)

Yes

No

1

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to the Powertrain On Board Diagnostic (OBD) System Check

2

  1. Turn OFF the ignition switch.
  2. Disconnect the PCM.
  3. Turn ON the ignition switch.
  4. Using a J 39200 Digital Multimeter, measure voltage between the EVAP canister purge valve control circuit at the PCM harness connector and ground.

Is voltage near the specified value?

B+

Go to Step 3

Go to Step 6

3

  1. Connect the digital multimeter to measure current between the EVAP canister purge valve control circuit at the PCM harness connector and ground.
  2. Monitor the current reading on the digital multimeter for at least 2 minutes.

Does the current reading remain between the specified values?

0.05-0.5 amps

(50-500 mA)

Go to Step 11

Go to Step 4

4

  1. Turn OFF the ignition switch.
  2. Disconnect the EVAP purge valve (leave the PCM disconnected).
  3. Turn ON the ignition switch.
  4. Using the digital multimeter, measure voltage between the EVAP canister purge valve control circuit and ground.

Is voltage at the specified value?

0 V

Go to Step 10

Go to Step 5

5

Locate and repair short to voltage in the EVAP canister purge valve control circuit. Refer to Wiring Repairs .

Is action complete?

--

Go to Step 16

--

6

Check the ignition feed fuse for the EVAP canister purge valve.

Is the fuse blown?

--

Go to Step 7

Go to Step 8

7
  1. Locate and repair short to ground in ignition feed circuit for the EVAP canister purge valve. Refer to Fuse Block Details in Electrical Diagnosis.
  2. Replace the fuse.

Is action complete?

--

Go to Step 16

--

8
  1. Disconnect the EVAP canister purge valve.
  2. Turn ON the ignition switch.
  3. Measure voltage between the ignition feed circuit for the EVAP canister purge valve and ground.

Is voltage near the specified value?

B+

Go to Step 9

Go to Step 13

9
  1. Check the EVAP canister purge valve control circuit for an open or a short to ground.
  2. If a problem is found, repair the EVAP canister purge valve control circuit. Refer to Wiring Repairs .

Was a problem found?

--

Go to Step 16

Go to Step 10

10
  1. Check for the following conditions:
    2. • The EVAP purge valve control circuit for a poor connection at the PCM.
    • The EVAP purge valve control circuit for a poor connection at EVAP purge valve.
    • The EVAP purge valve ignition feed circuit for a poor connection at the EVAP purge valve.
  2. If a problem is found, replace loose terminal(s) as necessary. Refer to Wiring Repairs .

Was a problem found?

--

Go to Step 16

Go to Step 14

11
  1. Turn OFF the ignition switch.
  2. Reconnect the PCM.
  3. Disconnect the EVAP canister purge valve.
  4. Turn ON the ignition switch.
  5. Connect a test light between the EVAP canister purge valve control circuit and the ignition feed circuit at the EVAP canister purge valve harness connector.
  6. Using the scan tool outputs test function, cycle the EVAP canister purge valve output ON and OFF.

Does the test light flash ON and OFF?

--

Refer to Diagnostic Aids

Go to Step 12

12
  1. Check the EVAP canister purge valve control circuit for a poor connection at the PCM.
  2. If a problem is found, replace loose terminal. Refer to Wiring Repairs .

Was a problem found?

--

Go to Step 16

Go to Step 15

13

Locate and repair open in ignition feed circuit to the EVAP canister purge valve. Refer to Wiring Repairs .

Is action complete?

--

Go to Step 16

--

14

Replace the EVAP canister purge valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement .

Is action complete?

--

Go to Step 16

--

15

Important:: Replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming .

Replace the PCM.

Is action complete?

--

Go to Step 16

--

16
  1. Review and record scan tool Fail Records data.
  2. Clear DTCs.
  3. Operate the vehicle within Fail Records conditions.
  4. Using a scan tool, monitor Specific DTC info for DTC P1676 until the DTC P1676 test runs.

Does the scan tool indicate DTC P1676 failed this ignition?

--

Go to Step 2

System OK