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Ecu Input Signals

  1. Timing control and triggering of the fuel injectors are based on input signals from the TDC/CRANK/CYL sensors. These sensors are simple Permanent Magnet (PM) generator pick-up coils.
  2. Using a DVOM (preferably with bar-graph function) on low-volt scale, check each sensor for pulse voltage signal at indicated ECU harness terminals with engine cranking. See ECU INPUT SIGNAL & RESISTANCE TEST TERMINALS  table. If pulse signal is present, sensor is okay. If pulse signal is not present, go to next step.
  3. Ensure ignition is off. Check wiring connections. Check resistance of each sensor at indicated ECU harness terminals. See ECU INPUT SIGNAL & RESISTANCE TEST TERMINALS  table. If resistance is not within specification, go to step 5). If resistance is within specification, go to next step.
    ECU INPUT SIGNAL & RESISTANCE TEST TERMINALS

    Application ECU Terminals (1) Resistance
    Integra
    CRANK B10 & B12 350-700 Ohms
    CYL C1 & C2 350-700 Ohms
    TDC C3 & C4 350-700 Ohms
    Legend
    CRANK No. 1 B15 & B16 600-950 Ohms
    CRANK No. 2 B14 & B13 600-950 Ohms
    CYL No. 1 B12 & B11 600-950 Ohms
    CYL No. 2 B9 & B10 600-950 Ohms
    (1) Terminal identifications are imprinted on ECU connector.
  4. Check continuity to ground on each terminal. If continuity exists, disconnect sensor connector, and recheck appropriate ECU terminal for continuity to ground. If continuity still exists, repair short to ground in harness. If continuity does not exist, replace sensor assembly.
  5. Disconnect sensor connector at sensor. See Fig 1 and Fig 2 . Check resistance of sensor. See ECU INPUT SIGNAL & RESISTANCE TEST TERMINALS  tables. If resistance is within specification, repair open, short or corrosion in sensor harness between ECU and sensor. If sensor resistance is not within specification, replace sensor assembly.
    Fig 1: Identifying Sensor Connector Terminals (Integra)
    G90B15025Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 2: Identifying Sensor Connector Terminals (Legend)
    G91H16284Courtesy of AMERICAN HONDA MOTOR CO., INC.