EVAP System Test
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2002 Mazda Protege5, 2002 Mazda Protege, 2002 Mazda Millenia, 2002 Mazda MX-5 Miata, and 2002 Mazda MPV. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
The EVAP system test, which can be substituted for run Drive Cycle as an EVAP control system repair confirmation method, can be done while operating WDS (or equivalent scan tool) at idle instead of actually driving vehicle.
- Connect scan tool to DLC-2. DLC-2 is located under left side of instrument panel, left of steering column. Select EVAP test from Toolbox on Scan tool display and follow instructions. Check PIDs. Ensure BARO (21.3 in. Hg or more), FLT V (1.3-3.7 volts) and IAT (14-140°F) readings are within specification at pretest confirimation screen.
- Start engine and run at 3500 RPM for 200 seconds to warm up completely. Select Tick icon to start test. See Fig 1
. Ensure each result is within specification, using FTL_V PID recorded in step 1). If scan tool values are not within specification, diagnose problem using DTC/SYSTEM TROUBLESHOOTING
table.DTC/SYSTEM TROUBLESHOOTING
Failure Troubleshoot Small Leak (A) DTC P0442 Very Small Leak (mA) DTC P0456 IMO (1) COV (2) (1) Inspect for open circuit or short to ground between PCM and EVAP system leak detection pump. (2) Inspect Change Over Valve (COV) to ensure valve is not stuck closed. - Check LDP_SLDV PID value. If LDP_SLDV PID value is lower than specified in Fig 1
and Fig 2
, perform appropriate test:
- Small Leak
See DTC P0442: EVAP SYSTEM LEAK DETECTED - SMALL LEAK in SELF-DIAGNOSTICS - MPV article. - Very Small Leak
See DTC P0456: EVAP SYSTEM LEAK DETECTED - VERY SMALL LEAK in SELF-DIAGNOSTICS - MPV article. - IMO (Air Pump Operation)
If LDP_REF PID value stay at zero volts during test. EVAP system leak detection pump circuit has electrical malfunction. See WIRING DIAGRAMS article. Repair or replace wiring harness as necessary. - COV (Change Over Valve Status)
If LDP_REF/LDP_IDL PID value is lower than 0.002 A, Change over valve is stuck closed. See DTC P0446: EVAP SYSTEM VENT CONTROL - MALFUNCTION in SELF-DIAGNOSTICS - MPV article.
- Small Leak