Engine Control Module (J220) Ground & Power Circuits: Notes

NOTE: Before performing test procedure, ensure battery voltage is a minimum of 11.5 volts. Manufacturer recommends using Scan Tool VAG 1551/1552 or VAS 5051/5052. The following tests are preformed using Scan Tool VAG 1551/1552 or 5051/5052. For location of Data Link Connector (DLC), see DATA LINK CONNECTOR .

NOTE: When voltage supply to Engine Control Module (ECM) (J220) is interrupted, ECM looses all "learned" and/or "basic" values. Serious driveability problems may occur depending on vehicle mileage. A relearn procedure must be performed, see TEST DRIVE RELEARN PROCEDURE .

NOTE: If a test ends with ECM replacement. Before replacing ECM be certain that, all wiring, power and ground supplies are okay. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.