Horn System: Inspection

INSPECT HORN SWITCH
1. Check that no continuity exists between terminal 6 of the connector and body ground.
2. Check that continuity exists between terminal 6 of the connector and body ground when the horn contact plate is pressed against the steering spoke assembly.
  If the continuity is not as specified, repair or replace the steering wheel or wire harness as necessary.
  
  Fig 1: Inspecting Horn Switch
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT HORN OPERATION
Connect the positive (+) lead from the battery to the terminal and negative (-) lead to the horn body and check that the horn blows.

If the operation is not as specified, replace the horn.

Fig 2: Inspecting Horn Operation
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT HORN RELAY CONTINUITY

Fig 3: Inspecting Horn Relay Continuity
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 4: Horn Relay Continuity Specifications
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the continuity is not as specified, replace the relay.