The evaporative emission control system prevents hydrocarbon (HC) vapors from the fuel tank from escaping into the atmosphere where they could form photochemical smog. Gasoline vapors are collected in the charcoal canister. The PCM controls the Purge Control Solenoid Valve (PCSV) to purge any collected vapors from the canister back to the engine for combustion. This valve is actuated by the purge control signal from the PCM and controls fuel vapor flow from the canister to the intake manifold.
PCM sets DTC P0444 if the PCM detects that the PCSV control circuit is open.
Item
Detecting Condition
Possible Cause
DTC Strategy
Electrical Check
Open in PCSV harness
Poor connection or damaged harness
Faulty PCSV
Enable Conditions
10V < Battery voltage < 16V
2% < Canister purge duty < 98%
Threshold Value
Open in control circuit
Diagnostic Time
3 sec.
MIL On Condition
2 Drive Cycles
Temp.(?)
PCSV Resistance(?)
20
68
19 ~ 22
? PCSV Control Waveform (Key-On)
? PCSV Control Waveform (Idle)
? PCSV Control Waveform (Control Circuit Open / Key-On / PCM Side)