The ECM contains no repairable parts. Calibrations stored in ECM read memory (PROM).
The ECM supplies either 5 or 12 volts to power the sensors and switches. This operation is performed by means of a resistance in the ECM that is so high that the test lamp will not come on when it is connected to the circuit. In some cases, a conventional industrial voltmeter will not be able to provide accurate readings due to too low self-resistance. You must use a digital voltmeter with a 10 megaohm input impedance for accurate readings. The ECM controls the output circuits of the fuel injectors, idle airflow valve, A/C clutch relay, etc. by driving the ground circuit through transistors or a device called «quaddriver» (quad driver).
Withdrawal
1. Disable «-» battery wire.
2. Disconnect the connectors of the engine control unit (ECM).
3. Remove the ECM mounting bolts.
4. Remove the ECM from the mounting surface.
Installation
1. Reinstall the ECM.
2. Install the ECM and tighten the ECM mounting screws to 4 Nm.
3. Connect «-» battery wire
4. Perform a camshaft position system deviation registration check.