Check Engine
The IPC illuminates the MIL telltale when the ECM detects a malfunction in the engine emission system. The MIL indicates that an emission related malfunction has occurred and vehicle service is required. The MIL telltale is hardwired to the ECM and the ECM will ground the MIL control circuit when it wants the indicator illuminated in the IPC. Refer to Engine Control Module (ECM) Description in Engine Controls.