System Check
Intake Manifold Communication Control (IMCC) actuator valve opens above 3750 RPM and closes again above 5500 RPM. Valve is normally closed. Using NGS scan tool, check for DTCs. If DTC P0660 is present, see DTC P0660: INTAKE MANIFOLD COMMUNICATION CONTROL testing procedure in SELF-DIAGNOSTICS - MPV article. If DTC P0660 is not present, check IMCC actuator operation. Remove IMCC actuator. Using fused jumper wires, connect battery voltage to IMCC connector terminals. Ensure actuator operates properly. See Fig 1 . If IMCC actuator does not operate as specified, replace IMCC actuator. If IMCC actuator operates as specified, check for open or short circuit. Disconnect PCM, IMCC actuator and main relay harness connectors and check for open circuit in wire harness:
- Red/Black wire between PCM harness connector terminal No. 28 and IMCC harness connector terminal "B".
- Between main relay 4-pin harness connector terminal "D" (Yellow wire) and IMCC actuator harness connector terminal "A" (White/Red wire).
Check for short circuit at following:
- Between IMCC actuator harness connector terminal "A" (White/Red wire) and ground.
- Between IMCC actuator harness connector terminal "B" (Red/Black wire) and power.
- Between IMCC actuator harness connector terminal "B" (Red/Black wire) and ground.
Repair or replace wire harness as necessary.