P0497
DTC P0497: EVAP System Low Purge FlowSpecial Tools Required
Vacuum pump/gauge, 0 - 30 in.Hg, Snap-on YA4000A or equivalent, commercially available
1. Turn the ignition switch ON (II).
2. Measure voltage between ECM connector terminal A6 and body ground.
Is there battery voltage?
YES - Go to step 3.
NO - Go to step 8.
3. Turn the ignition switch OFF.
4. Disconnect the vacuum hose (A) from the EVAP canister purge line (B) and connect a vacuum pump/gauge, 0 - 30 in.Hg, to the hose.
5. Connect ECM connector terminal A6 to body ground with a jumper wire.
6. Turn the ignition switch ON (II).
7. Apply vacuum to the hose.
Does the valve hold vacuum?
YES - Replace the EVAP canister purge valve.
NO - Go to step 16.
8. Turn the ignition switch OFF.
9. Disconnect ECM connector A (32P).
10. Connect ECM connector terminal A6to body ground with a jumper wire.
11. Disconnect the EVAP canister purge valve 2P connector.
12. Check for continuity between EVAP canister purge valve 2P connector terminal No.2 and body ground.
Is there continuity?
YES - Go to step 13.
NO - Repair open in the wire between the EVAP canister purge valve and the ECM (A6).
13. Turn the ignition switch ON (II).
14. Measure voltage between EVAP canister purge valve 2P connector terminal No.1 and body ground.
Is there battery voltage?
YES - Go to step 15.
NO - Repair open in the wire between the EVAP canister purge valve and the No.4 (7.5 A) fuse in the under-dash fuse/relay box.
15. At the sensor side, measure resistance between EVAP canister purge valve 2P connector terminals No.1 and No.2.
Is there about 33 ohm at room temperature?
YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
NO - Replace the EVAP canister purge valve.
16. Measure voltage between ECM connector terminal A4 and body ground.
Is there battery voltage?
YES - Go to step 17.
NO - Go to step 22.
17. Turn the ignition switch OFF.
18. Disconnect the vacuum hose from the EVAP canister vent filter line (A), and connect a vacuum pump/gauge, 0 - 30 in.Hg, to the hose.
19. Connect ECM connector terminal A4 to body ground with a jumper wire.
20. Turn the ignition switch ON (II).
21. Apply vacuum to the hose.
Does the valve hold vacuum?
YES - Inspect the vacuum line between the EVAP canister purge valve and the EVAP canister.
NO - Replace the EVAP canister vent shut valve.
22. Turn the ignition switch OFF.
23. Disconnect ECM connector A (32P).
24. Connect ECM connector terminal A4 to body ground with a jumper wire.
25. Disconnect the EVAP canister vent shut valve 2P connector.
26. Check for continuity between EVAP canister vent shut valve 2P connector terminal No.2 and body ground.
Is there continuity?
YES - Go to step 27.
NO - Repair open in the wire between the EVAP canister vent shut valve and the ECM (A4).
27. Turn the ignition switch ON (II).
28. Measure voltage between EVAP canister vent shut valve 2P connector terminal No.1 and body ground.
Is there battery voltage?
YES - Go to step 29.
NO - Repair open in the wire between the EVAP canister vent shut valve and the No.4 (7.5 A) fuse in the under-dash fuse/relay box.
29. At the sensor side, measure resistance between EVAP canister vent shut valve 2P connector terminals No.1 and No.2.
Is there about 33 ohm at room temperature?
YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
NO - Replace the EVAP canister vent shut valve.