Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL KL]
DTC P1451 Canister drain cut valve (CDCV) malfunction
DESCRIPTION
• DTC P1451 indicates that self-test has detected Canister Drain Cut Valve (CDCV) circuit
failure.
[Possible Cause]
• Damaged fuel tank pressure (FTP) sensor • CDCV circuit open
• Kinks or blockage in fuel vapor hose/tube between fuel • CDCV circuit shorted to ground circuit
tank, purge solenoid valve and fuel vapor storage • CDCV circuit shorted to power circuit
canister(s) or between fuel vapor storage canlster(s), • Damaged CDCV
CDCV and atmosphere • Damaged PCM
• Power circuit circuit open
STEP
INSPECTION ACTION
1
CHECK FOR POWER CIRCUIT TO CDCV
• Key off.
• Disconnected CDCV vehicle harness
connector.
• Key on, engine off.
• Measure voltage between power circuit at
CDCV vehicle harness connector and
battery ground.
• Is voltage greater than 1
0.5
volts?
Yes Go to next step.
No SERVICE open in power circuit harness to CDCV.
RECONNECT all components.
RESET PCM to completely clear DTCs.
xt
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
2
CHECK CDCV RESISTANCE
• Key off.
• Disconnect CDCV connector.
• Measure resistance between CDCV and
power circuit on CDCV.
• Is resistance between
45
and
65
ohms?
Yes
Go to next step.
No REPLACE damaged CDCV.
RECONNECT CDCV. RECORD and REMEMBER this
Pinpoint Test Step.
Go to step 8.
Then RETURN to Pinpoint test Step that directed you
here.
RESET PCM to completely clear DTCs.
x t
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
3 CHECK RESISTANCE OF CDCV CIRCUIT
•
Key off.
•
Disconnect CDCV and PCM. Inspect for
damaged or pushed out pins, corrosion
and loose wires. Service as necessary.
•
Install breakout box. Leave PCM
disconnected.
•
Measure resistance between Test Pin 18 at
breakout box and CDCV circuit at CDCV
vehicle harness connector.
• Is resistance less than 5.0 ohms?
Yes Go to next step.
No
SERVICE open in CDCV harness.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
x t
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
4 CHECK CDCV CIRCUIT FOR SHORT TO
GROUND CIRCUIT
•
Key off.
•
CDCV disconnected.
•
Breakout box installed.
•
PCM disconnected.
•
Disconnected NGS tester from DLC.
•
Measure resistance between Test Pin 18
and Test Pins 51 and 103 at breakout box.
•
Is resistance greater than 10,000 ohms?
Yes RECONNECT NGS tester. Go to next step.
No
SERVICE harness short between CDCV and ground
circuit.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
it
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
5
CHECK CDCV SIGNAL CIRCUIT FOR
SHORT TO POWER CIRCUIT
• Key off.
• CDCV disconnected.
• Breakout box installed, PCM disconnected.
• Key on, engine off.
• Measure voltage between Test Pin
1
8 at
breakout box and chassis ground.
• is voltage less than
1
.0
volts?
Yes Go to next step.
No
SERVICE harness short between CDCV and power circuit
(power circuit, constant voltage or chassis ground).
RECONNECT all components.
RESET PCM to completely clear DTCs.
x t
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
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