ECM Circuit Check

CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. Check following terminals and connector for damage, bent or loose connection (control module-side and harness-side).
  - ECM.
  - Harness connector F59.
  - Harness connector M71.
    OK or NG
    1. OK : GO TO 2.
    2. NG : Repair terminal or connector.
CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect ECM connector.
2. Check the following.
  - Resistance between ECM harness connector F54 terminals 94 (L) and 86 (Y) (QR25DE models).
  - Resistance between ECM harness connector F54 terminals 109 (L) and 113 (Y) (VQ35DE models).
    94 (L) - 86 (Y) (QR25DE models) : Approx. 108 - 132Ω
    
    109 (L) - 113 (Y) (VQ35DE models) : Approx. 108 - 132Ω
    
    OK or NG
    1. OK : Replace ECM.
    2. NG : Repair harness between harness connector M7 and ECM.
      
      Fig 1: Checking Resistance Between ECM Harness Connector F54 Terminals
      Courtesy of NISSAN MOTOR CO., U.S.A.