ECM Harness Resistance

Turn ignition switch to LOCK position. Disconnect ECM and related component harness connectors. Check for open or short circuits between ECM harness connector terminal and component harness connector terminal. For connector terminal identification, see Fig 1 -Fig 6 . See WIRING DIAGRAMS  . If harness is open or shorted, repair as necessary.

Fig 1: Identifying ECM Connector C1 Terminals (1 Of 3)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Identifying ECM Connector C1 Terminals (2 Of 3)

Courtesy of GENERAL MOTORS CORP.

Fig 3: Identifying ECM Connector C1 Terminals (3 Of 3)

Courtesy of GENERAL MOTORS CORP.

Fig 4: Identifying ECM Connector C2 Terminals (1 Of 3)

Courtesy of GENERAL MOTORS CORP.

Fig 5: Identifying ECM Connector C2 Terminals (2 Of 3)

Courtesy of GENERAL MOTORS CORP.

Fig 6: Identifying ECM Connector C2 Terminals (3 Of 3)

Courtesy of GENERAL MOTORS CORP.