Inspection Procedure

1. Connect the battery's positive (+) lead to the terminal, and the negative (-) lead to the horn body.
   Fig 1: Connecting Battery's Positive (+) Lead To Terminal, And Negative (-) Lead To Horn Body

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2. Check that the horn sounds

   Standard: Horn sounds 

1. NG: REPAIR OR REPLACE HORN ASSY 

OK: Go to next step 

1. Remove the HORN relay from the engine room R/B.
   Fig 2: Removing Horn Relay From Engine Room R/B

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2. Measure the resistance of the relay.
   TESTER CONNECTION SPECIFIED CONDITION CHART (1 OF 3)
   
   

   Tester Connection	Specified Condition
   3-5	10 kΩ or higher
   3-5	Below 1 Ω (when battery voltage is applied to terminals 1 and 2)

   1. NG: REPLACE RELAY 

OK: Go to next step 

1. Remove the HORN relay from the engine room R/B.
2. Disconnect the T3 TVIP ECU connector.
   Fig 3: Disconnecting T3 TVIP ECU Connector

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3. Measure the resistance of the wire harness side connectors.
   TESTER CONNECTION SPECIFIED CONDITION CHART (2 OF 3)
   
   

   Tester Connection	Specified Condition
   HORN (T3-5) - R/B HORN relay terminal 2	Below 1 Ω

1. NG: REPAIR OR REPLACE WIRE HARNESS AND CONNECTOR 

OK: Go to next step 

Fig 4: Identifying Engine Room R/B AND J/B - Horn Connector

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1. Remove the HORN relay from the engine room R/B.
2. Disconnect the HORN connector.
   TESTER CONNECTION SPECIFIED CONDITION CHART (3 OF 3)
   
   

   Tester Connection	Specified Condition
   R/B HORN relay terminal 3 - HORN (H6-1 )	Below 1 Ω

1. NG: REPAIR OR REPLACE WIRE HARNESS AND CONNECTOR 

OK: Go to next step 

CHECK AND REPLACE TVIP ECU (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  )