IMCC System Inspection
- Intake Manifold Communication Control (IMCC) actuator valve opens above 3750 RPM and closes again above 5500 RPM. Valve is normally closed. Using 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 actuator connector terminals. Ensure IMCC actuator operates properly. See Fig 1. If IMCC actuator operates as specified, check for open or short circuit. Go to next step. If IMCC actuator does not operate as specified, replace IMCC actuator.
- Open Circuit Inspection
Disconnect PCM, IMCC actuator and main relay harness connectors. Check for continuity between following terminals:- PCM 104-pin harness connector terminal No. 28 and IMCC actuator 2-pin harness connector terminal "B" (Red/Black wire).
- Main relay 4-pin harness connector terminal "D" (Yellow wire) and IMCC actuator harness connector terminal "A" (White/Red wire).
If continuity is present, go to next step. If continuity is not present, repair open circuit in suspect wire or replace wire harness. See appropriate WIRING DIAGRAM under ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS.
- Short Circuit Inspection
Check for continuity between following:- IMCC actuator harness connector terminal "A" (White/Red wire) and ground.
- IMCC actuator harness connector terminal "B" (Red/Black wire) and power.
- IMCC actuator harness connector terminal "B" (Red/Black wire) and ground.
If continuity is present, repair short circuit in suspect wire or replace wire harness.