ECM Circuit Check

WARNING: This page is about a different car, the 2003 Nissan Altima. However, it is still accessible from the selected car via links, so may be relevant.

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 33 (L) and 34 (Y) (QR25DE models).
- Resistance between ECM harness connector F54 terminals 109 (L) and 113 (Y) (VQ35DE models).
  33 (L) - 34 (Y) (QR25DE models) : Approx. 108 - 132Ω
  
  109 (L)- 113 (Y) (VQ35DE models) : Approx. 108 - 132Ω
  
  Fig 1: Checking Resistance Between ECM Harness Connector F54 Terminals
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: Replace ECM.
2. NG: Repair harness between harness connector M7 and ECM.