DTC Troubleshooting
DTC Troubleshooting: P0443, P0443
DTC P0443:
EVAP Canister Purge Valve Circuit Malfunction
Special Tools Required
- Vacuum Pump/Gauge, 0-30 inHg Snap-on YA4000A or equivalent, commercially available
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information Initial Inspection and Diagnostic Overview.
1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle.
4. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0443 indicated?
YES -
Go to step 5.
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the EVAP canister purge valve and the ECM/PCM.�
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode and allow the engine to cool to below 140 °F (60 °C).
6. Disconnect the vacuum hose (A) from the purge joint (B) in the engine compartment, and connect a vacuum pump/gauge, 0-30 inHg, to the hose.
7. Start the engine, and let it idle.
Is there vacuum?
YES -
Go to step 8.
NO -
Go to step 14.
8. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
9. Disconnect the EVAP canister purge valve 2P connector.
10. Check for continuity between EVAP canister purge valve 2P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Go to step 11.
NO -
Go to step 23.
11. Jump the SCS line with the HDS.
12. Disconnect ECM/PCM connector C (49P).
13. Check for continuity between EVAP canister purge valve 2P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Repair short in the wire between the EVAP canister purge valve and the ECM/PCM (C40), then go to step 24.
NO -
Go to step 30.
14. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
15. Disconnect the EVAP canister purge valve 2P connector.
16. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
17. Measure the voltage between EVAP canister purge valve 2P connector terminal No. 2 and body ground.
Is there battery voltage?
YES -
Go to step 18.
NO -
Repair open in the wire between the EVAP canister purge valve and the No. 13 ACG (15 A) fuse in the driver's under-dash fuse/relay box, then go to step 24.
18. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
19. Jump the SCS line with the HDS.
20. Disconnect ECM/PCM connector C (49P).
21. Check for continuity between ECM/PCM connector terminal C40 and EVAP canister purge valve 2P connector terminal No. 1.
Is there continuity?
YES -
Go to step 22.
NO -
Repair open in the wire between the EVAP canister purge valve and the ECM/PCM (C40), then go to step 24.
22. At the valve side, measure the resistance between EVAP canister purge valve 2P connector terminals No. 1 and No. 2.
Is there about 23-26 Ohms at room temperature?
YES -
Go to step 30.
NO -
Go to step 23.
23. Replace the EVAP canister purge valve .
24. Reconnect all connectors.
25. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
26. Reset the ECM/PCM with the HDS.
27. Do the ECM/PCM idle learn procedure ECM/PCM Idle Learn Procedure.
28. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0443 indicated?
YES -
Check for poor connections or loose terminals at the EVAP canister purge valve and the ECM/PCM, then go to step 1.
NO -
Go to step 29.
29. Monitor the OBD STATUS for DTC P0443 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 28, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the EVAP canister purge valve and the ECM/PCM, then go to step 1. If the screen indicates EXECUTING or OUT OF CONDITION, keep idling until a result comes on.
30. Reconnect all connectors.
31. Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM.
32. Start the engine, and let it idle.
33. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0443 indicated?
YES -
Check for poor connections or loose terminals at the EVAP canister purge valve and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then go to step 32. If the ECM/PCM was substituted, go to step 1.
NO -
Go to step 34.
34. Monitor the OBD STATUS for DTC P0443 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair. If any other Pending or Confirmed DTCs were indicated in step 33, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the EVAP canister purge valve and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then go to step 32. If the ECM/PCM was substituted, go to step 1. If the screen indicates EXECUTING or OUT OF CONDITION, keep idling until a result comes on.