Mazda CX-7 2007 Workshop Manual page 185

DTC P0446 Change over valve (COV) (EVAP system leak detection pump) stuck close
MAIN RELAY
EVAP SYSTEM LEAK DETECTION PUMP
WIRING HARNESS-SIDE CONNECTOR
C
D
Diagnostic procedure
STEP
1 VERIFY FREEZE FRAME DATA AND
DIAGNOSTIC MONITORING TEST RESULTS
HAVE BEEN RECORDED
• Have the FREEZE FRAME DATA and
DIAGNOSTIC MONITORING TEST RESULTS
(EVAP system related) been recorded?
2 VERIFY RELATED REPAIR INFORMATION
AVAILABILITY
• Check for related Service Bulletins and/or on-
line repair information availability.
• Is any related repair information available?
3 CHECK COV CONTROL (EVAP SYSTEM LEAK
DETECTION PUMP CIRCUIT FOR SHORT TO
POWER)
• Turn ignition switch to the ON position (engine
OFF).
• Disconnect the EVAP system leak detection
pump connector.
• Measure the voltage between EVAP system
leak detection pump connector terminal C
(wiring harness-side) and body ground.
• Is the voltage B+?
4 INSPECT COV (EVAP SYSTEM LEAK
DETECTION PUMP)
• Inspect the EVAP system leak detection pump.
(See01-16-7 EVAPORATIVE EMISSION
(EVAP) SYSTEM LEAK DETECTION PUMP
INSPECTION[L3 WITH TC].)
• Is the COV (EVAP system leak detection
pump) normal?
ON-BOARD DIAGNOSTIC [L3 WITH TC]
EVAP SYSTEM LEAK
DETECTION PUMP
A C
M
D
B
4
1BE 1BA 1AW 1AS 1AO 1AK 1AG 1AC 1Y 1U 1Q 1M
A
1BF 1BB 1AX 1AT 1AP 1AL 1AH 1AD 1Z 1V 1R 1N
B
1BG 1BC 1AY 1AU 1AQ 1AM 1AI 1AE 1AA 1W 1S 1O
1BH 1BD 1AZ 1AV 1AR 1AN 1AJ 1AF 1AB 1X
INSPECTION
PCM
3
1V
1AS
PCM WIRING
HARNESS-SIDE CONNECTOR
Yes Go to the next step.
No Record FREEZE FRAME DATA and DIAGNOSTIC
MONITORING TEST RESULTS on the repair order, then
go to the next step.
Yes Perform the repair or diagnostic according to the available
repair information.
• If the vehicle is not repaired, then go to the next step.
No Go to the next step.
Yes Repair or replace the wiring harness, then go to Step 5.
No Go to the next step.
Yes Go to the next step.
No Replace the EVAP system leak detection pump, then go to
the next step.
1I 1E 1A
1J 1F 1B
1K 1G 1C
1T 1P 1L 1H 1D
ACTION
01-02–143
01-02