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Relay Circuit Board Test (3.0L Engine): Test

How to use this service information .

NOTICE: 

When working with a vehicle equipped with the electronic air suspension, be sure to set it to the leveling off mode to prevent unexpected operation. Refer to the Electronic Air Suspension System Service Precautions - Refer to: Electronic Air Suspension System Connector Fitting Precautions or Electronic Air Suspension System Service Precautions for the procedure.

  1. Relay Circuit Board Test

    Preconditions 

    • Relay Circuit Board Removed
    GHH514864Courtesy of HONDA, U.S.A., INC.

    Procedure/Specifications 

    The relay circuit board is part of the under-hood fuse/relay box, and it contains these relay circuits diodes:

    • Radiator Fan Motor Diode
    • Condenser Fan Motor Diode
    • Starter Cut Relay 1 Circuit
    • Starter Cut Relay 2 Circuit
    • Brake Light Relay Circuit
    • Windshield Washer Motor Relay Circuit
    • Rear Window Washer Motor Relay Circuit

    NOTICE: 

    • When an LED is located between terminals, check if the LED lights up by connecting power and ground to the LED.
    • When checking for continuity across the diode, use the diode setting ( ) on the digital volt/ohm meter to check the diode bias.
    • Note this important operating characteristic; diode bias causes a diode to fully conduct electricity in one direction (forward), while not at all in the opposite direction (reverse).

    Radiator Fan Motor Diode and Condenser Fan Motor Diode 

    Radiator Fan Motor Diode

    • There should be continuity between terminals A4 and A13.

    Condenser Fan Motor Diode

    • There should be continuity between terminals A3 and A12.
    GHH514866Courtesy of HONDA, U.S.A., INC.

    Starter Cut Relay 1 Circuit and Starter Cut Relay 2 Circuit 

    Starter cut relay 1 circuit

    • There should be continuity between terminals A6 and B3, when 12 volt battery power is connected to terminal B12, and body ground is connected to terminal B7.
    • There should be no continuity between terminals A6 and B3 when terminal B7 is disconnected.

    Starter cut relay 2 circuit

    • There should be continuity between terminals B2 and B3, when 12 volt battery power is connected to terminal B12, and body ground is connected to terminal B8.
    • There should be no continuity between terminals B2 and B3 when terminal B8 is disconnected.
    GHH514867Courtesy of HONDA, U.S.A., INC.

    Brake Light Relay Circuit 

    Brake Light Relay Circuit

    • There should be continuity between terminals A14 and B1, when 12 volt battery power is connected to terminal B11, and body ground is connected to terminal A11.
    • There should be no continuity between terminals A14 and B1, and there should be continuity between terminals A2 and B1 when terminal A11 is disconnected.
    GHH514868Courtesy of HONDA, U.S.A., INC.

    Windshield Washer Motor Relay Circuit and Rear Window Washer Motor Relay Circuit 

    Windshield Washer Motor Relay Circuit

    • There should be battery voltage at terminal A1 when 12 volt battery power is connected to terminal A5, and body ground is connected to terminal A16.
    • There should be no voltage at terminal A1 when terminal A16 is disconnected.
    • There should be continuity between terminals A1 and A18, when 12 volt battery power is not connected to anything.

    Rear Window Washer Motor Relay Circuit

    • There should be battery voltage at terminal A10 when 12 volt battery power is connected to terminal A5, and body ground is connected to terminal A17.
    • There should be no voltage at terminal A10 when terminal A17 is disconnected.
    • There should be continuity between terminals A10 and A18, when 12 volt battery power is not connected to anything.
    GHH514869Courtesy of HONDA, U.S.A., INC.

    Result