Diagnosis Procedure
1.Check connector
Is the inspection result normal? YES >> GO TO 2.
NO >> Repair the terminal and connector.
2.Check harness for open circuit

Is the measurement value within the specification? Yes >> go to 3.
No >> repair the ecm branch line.
3.Check power supply and ground circuit
Check the power supply and the ground circuit of the ecm. Refer to ec-164, "diagnosis procedure".
Is the inspection result normal? Yes (present error)>>replace the ecm. Refer to ec-485, "removal and installation".
Yes (past error)>>error was detected in the ecm branch line.
No >> repair the power supply and the ground circuit.
Main line between dlc and hvac circuit
Abs branch line circuitFuel (Regular Unleaded Gasoline Recommended)
Use unleaded regular gasoline with an octane rating of at least 87 AKI
(Anti-Knock Index) number (Research
octane number 91). E-85 fuel (85% fuel ethanol, 15% unleaded gasoline) may only
be used in vehicles specifically
designed for E-85 fuel (i.e. Flexible Fuel Vehicle - FFV models).
CAUTION ...
Ecu diagnosis information
Ipdm e/r (intelligent power distribution module engine room)
Reference Value
Values on the diagnosis tool
Terminal layout
Physical values
Fail-safe
Can communication control
When CAN communication with ECM and BCM is impossible, IPDM E/R performs
fail-safe ...
P1800 Intake manifold tuning valve
DTC Logic
DTC DETECTION LOGIC
DTC No.
CONSULT screen terms
(Trouble diagnosis content)
DTC detecting condition
Possible cause
P1800
VIAS S/V-1
(Variable intake air system control
solenoid valve-1)
An excessively low or high voltage signal
is sent to ECM t ...