Workshop Manual

11.8 Failure in Driver Stage of Canister Control Valve
Failure codes: P0443, 0444, 0445
No. Operating steps Result Follow up steps
1 Start the engine and let it run at idle speed until
engine coolant temperature reaches normal value.
Next step
Yes Next step 2 Pull out canister control valve joint on harness;
use a multimeter to check if an around 8.6V
battery voltage is present between two pins of this
joint.
No 5 (check positive
wire)
Yes Next step 3 Re-plug the canister control valve joint on harness,
increase engine revolution to 2000rpm, and then
touch the valve body by hand to check if the
canister control valve has slight vibration and
impact (frequency control).
No 7 (check ground
wire)
Yes Replace ECU 4 Use a multimeter to check if the resistance value
between A# and B# pins of the canister control
valve is around 25Ω (20).℃
No Replace the canister
control valve
Yes Repair or replace
the harness
5 Check if it is short circuit or break circuit between
the pin of main relay 87# and the pin of canister
control valve 1# with multimeter.
No Next step
6 Repair or replace the main relay and the circuit.
Yes Repair or replace
harness
7 Cut off the engine; connect the adaptor between
ECU and harness, and use a multimeter to check if
it is break or short circuit between 46# pin of ECU
and A# pin of the canister control valve.
No Replace ECU
8 With ignition switch ON, disconnect canister
control valve joint, and then use a multimeter to
check the A# and B# pins at harness end of
solenoid valve.
Next step
Yes Next step 9 Use a multimeter to check if an around 12V
battery voltage is present between B# pin and
ground wire.
No Check feed circuit
Yes Check other part 10 Use a multimeter to check if an around 3.6V
battery voltage is present between A# pin and
ground wire.
No
Check ECU circuit
or replace the ECU
Note: The carbon canister solenoid valve is used for the emission control system, a
system set up for environmental protection and air pollution prevention. When engine
runs at idle speed or under heavy load operating mode, the solenoid valve will not
participate in the work. A malfunction of this solenoid valve will result in unsteady
operating mode of the engine. These details should be noted during maintenance
process.