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Relay Control Module Test

The relay control module is part of the under-hood fuse/relay box, and it contains these relays:

If any of these relays fail the test, replace the under-hood fuse/relay box.

  1. Do the battery terminal disconnection procedure (see USING THE GR8 BATTERY DIAGNOSTIC STATION ), then disconnect under-hood fuse/relay box connectors C (2P), E (14P), and H (9P).
    NOTE: All connector views are wire side of female terminals.
    Fig 1: Identifying Under-Hood Fuse/Relay Box Connectors C (2P)
    G08053766Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 2: Identifying Under-Hood Fuse/Relay Box Connectors E (14P)
    G08053767Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 3: Identifying Under-Hood Fuse/Relay Box Connectors H (9P)
    G08053768Courtesy of AMERICAN HONDA MOTOR CO., INC.
  2. Connect battery power to terminal C2.

    PGM-FI main relay 1:

    • Connect terminal E5 to body ground. There should be battery voltage between terminal H1 and body ground.
    • Disconnect terminal E5 from the body ground. There should be no voltage between terminal H1 and the body ground.

    Ignition coil relay:

    • Connect terminal E5 to body ground. There should be battery voltage between terminal H6 and body ground.
    • Disconnect terminal E5 from the body ground. There should be no voltage between terminal H6 and the body ground.

    PGM-FI subrelay

    • Connect terminals E5 and E13 to body ground. There should be battery voltage between terminal H9 and body ground.
    • Disconnect terminal E5 from the body ground. There should be no voltage between terminal H9 and the body ground.

    ETCS control relay:

    • Connect terminals E5 and E14 to body ground. There should be battery voltage between terminal H7 and body ground.
    • Disconnect terminal E5 from the body ground. There should be no voltage between terminal H7 and body ground.
  3. Connect battery power to terminal H3.

    Horn relay:

    • Connect terminal E4 to body ground. There should be battery voltage between terminal H4 and body ground, and between terminal H5 and body ground.
    • Disconnect terminal E4 from the body ground. There should be no voltage between terminal H4 and body ground, and between terminal H5 and body ground.