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Engine Control Module: Installation

WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
  1. Install ECM. Install ECM bolts. Tighten ECM bolts to specification. See TORQUE SPECIFICATIONS  . Connect Jl and J2 ECM electrical connectors. Install outlet resonator/duct assembly into position. Connect PCV fresh air vent hose assembly.
  2. Install outlet resonator/duct assembly. See AIR CLEANER OUTLET RESONATOR/DUCT ASSEMBLY  . Connect negative battery cable. Tighten negative battery terminal bolt to specification. Reprogram preset radio stations and reset clock to correct time.
  3. If a new ECM is being installed, it must be reprogrammed with new software and calibrations. See ELECTRONIC CONTROL MODULE  under PROGRAMMING.
Fig 1: Locating Engine Control Module (2.2L)
G00165025Courtesy of GENERAL MOTORS CORP.


CAUTION: Over tightening battery cooling box bolts will break or crack the plastic.
  1. Install ECM and ECM attachment bolts, making sure the ground wire is attached between the upper front bolt and ECM case. Tighten ECM attachment bolts to specification. See TORQUE SPECIFICATIONS  .
  2. Connect ECM Jl and J2 harness connectors. Jl harness connector has more wires in its harness and is the connector closest to the front of the dash. Make sure the connectors are fully seated and locked into position. Position battery cooling box on tray so that inlet and outlet ducts are properly aligned. Alignment of inlet and outlet ducts with battery cooling box is critical to ensure proper airflow to battery.
  3. Install battery cooling box bolts. Tighten battery cooling box bolts to specification. Install battery cooling box side support bolt. Tighten battery cooling box side support bolt to specification. Connect forward lamp harness to UHFB and attach UHFB into housing.
  4. Install UHFB connector retaining bolts. Secure all cables, lines and harnesses into retaining clips. Attach positive battery cable and EPS wire to B+ terminal at UHFB and tighten nut. Tighten UHFB B+ terminal nut to specification. Insert battery and install battery hold-down bolt. Tighten battery hold-down bolt to specification.
  5. Connect positive battery cable to battery. Connect negative battery cable to battery. Tighten battery terminal bolts to specification. Install UHFB cover. Install battery cooling box cover and tighten screws. Reprogram radio stations and reset clock to correct time.
  6. If the ECM has been replaced, it must be reprogrammed with the correct software and calibrations. See ELECTRONIC CONTROL MODULE  under PROGRAMMING. Leave ignition on for 1 minute to enable the ECM to learn the throttle body. Turn ignition off for 10 seconds, and then turn ignition back on. Clear DTCs in all controllers. The ECM will automatically learn the crankshaft variation while driving. No manual procedure is required.
Fig 1: Removing/Installing Underhood Fuse Block & Battery Cooling Box (3.0L)
G00165026Courtesy of GENERAL MOTORS CORP.
Fig 2: Removing/Installing Engine Control Module (3.0L)
G00165021Courtesy of GENERAL MOTORS CORP.
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