Nissan 100NX N14 silhouetteN14

TROUBLE DIAGNOSES — Diagnostic Procedure

EF & EC-249prose procedure
Continued from EF & EC-248

Diagnostic Procedure

  1. 1
    Before connecting or disconnecting the E.C.U. harness connector to or from any E.C.U., be sure to turn the ignition switch to the "OFF" position and disconnect the negative battery terminal in order not to damage E.C.U. as battery voltage is applied to E.C.U. even if ignition switch is turned off. Failure to do so may damage the E.C.U.
    CAUTION
    Illustration of a vehicle battery with an arrow showing disconnection of the negative battery terminal cable.
    SEF289H
  2. 2
    When connecting E.C.U. harness connector, tighten securing bolt until red projection is in line with connector face.
    E.C.U. connector being mated to the unit, with callouts pointing to the "Red projection" on the connector and the "Protector" over the wiring harness.
    SEF725H
  3. 3
    When connecting or disconnecting pin connectors into or from E.C.U., take care not to damage pin terminals (bend or break).
    E.C.U. illustration showing two pin terminal conditions to avoid: a "Bend" and a "Break" of the pins, each with an arrow.
    SEF291H
  4. 4
    Make sure that there are not any bends or breaks on E.C.U. pin terminal, when connecting pin connectors.
  5. 5
    Before replacing E.C.U., perform E.C.U. input/output signal inspection and make sure whether E.C.U. functions properly or not. (See page EF & EC-343.)
    Cartoon-style illustration of a technician holding an "OLD ONE" E.C.U. with a speech bubble reading "Perform E.C.U. input/output signal inspection before replacement."
    SEF330D
  6. 6
    After performing this "Diagnostic Procedure", perform E.C.C.S. self-diagnosis and driving test.
    Cartoon-style illustration of an E.C.U. and a person performing E.C.C.S. self-diagnosis and driving test.
    SEF417J
Support our work!

See also

EF & EC-343Electrical Components Inspection - E.C.U. INPUT/OUTPUT SIGNAL INSPECTION

Search Manual

Search pages, specs, and procedures