Category Archives: GM 6.5

GM/Detroit 6.5L ENGINE CONTROLS – No Malfunction Indicator Lamp

Circuit Description There shoul d always be a steady malfunction indicator lamp (MIL) when the ignition is ON and the engine is OFF. Battery ignition voltage is supplied to the lamp. The PCM will turn the lamp ON by grounding the ignition feed circuit. Diagnostic Aids If the engine cranks but will not run, check:โ€ฆ Read More »