Contents: Removal ↧ Installation ↧
The Engine Control Module (ECM), located under the passenger dash, is the control center for the fuel injection system. It constantly monitors information from various sensors and controls systems that affect engine drivability. The ECM also performs diagnostics for the system. It recognizes operating problems, alerts the driver via the Malfunction Indicator Lamp (MIL), and stores trouble codes that identify problem areas to help a mechanic make repairs.
The ECM does not contain any parts that need to be repaired. Calibrations are stored in the ECM Read memory (PROM).
The ECM supplies either 5 or 12 volts to power the sensors and switches. This is done through a resistance in the ECM that is so high that the test lamp will not light when connected to the circuit. In some cases, a standard industrial voltmeter will not provide an accurate reading because its own resistance is too low. A digital voltmeter with an input resistance of 10 megohms must be used to obtain an accurate reading. The ECM controls the output circuits of the fuel injectors, idle air flow valve, air conditioning clutch relay, etc. by controlling the ground circuit through transistors or a device called "quaddriver".
Removal
1. Disconnect the "-" battery cable.
2. Disconnect the Engine Control Module (ECM) connectors
3. Remove the ECM mounting bolts.
4. Remove the ECM from the mounting surface.
Installation
1. Reinstall the ECM.
2. Install the ECM on the ECM setup program and install the splinter bolts. Tighten the ECM mounting bolts to 4 Nm.
3. Connect the "-" wire of the battery.
4. Perform a camshaft position system deviation range registration check.
(The original article is on the website: «chevyman»)