SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSTOYOTA2004MATRIX XR, FWD, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 437 (BODY CONTROL SYSTEMS - DIAGNOSTICS)CIRCUIT INSPECTIONTHEFT DETERRENT HORN CIRCUITINSPECTION PROCEDURE
2004 Toyota Matrix XR, FWD, Standard

Inspection Procedure

2004 Toyota Matrix XR, FWD, StandardSECTION Inspection Procedure
WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Steps 1-2 are based on the premise that the horns blow normally whenever the horn switch is operated. If horn operation is not normal when the horn switch is operated, check the horn switch.
  1. Check voltage between terminal 1 of theft deterrent horn connector and body ground. 
    Fig 1: Verifying Voltage At Horn Connector
    G01112598Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    PREPARATION: 

    Remove the theft deterrent horn and disconnect the connector.

    CHECK: 

    Measure voltage between terminal 1 of theft deterrent horn connector and body ground.

    OK: 

    Voltage: 10-14 V 

    1. NG: Check and repair harness and connector between HORN fuse and theft deterrent horn. 
    2. OK: Go to next step. 
  2. Check theft deterrent horn. 

    CHECK: 

    Connect positive (+) lead to terminal 1 and negative (-) lead to ground to theft deterrent horn connector.

    OK: 

    Theft deterrent horn blows. 

    Fig 2: Testing Horn By Applying Battery Voltage
    G01112599Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Replace theft deterrent horn. 
    2. OK: Go to next step. 
  3. Check harness and connector between body ECU and theft deterrent horn  . See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE .
    1. NG: Check and repair harness or connector. 
    2. OK: Go to next step. 

    Check and replace body ECU. 

RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.