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Home >> Mazda >> 2008 >> Tribute 2WD L4-2.3L >> Repair and Diagnosis >> Lighting and Horns >> Horn >> Testing and Inspection >> Pinpoint Tests >> Pinpoint Test 1
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Pinpoint Test 1

PINPOINT TEST 1: THE HORN IS INOPERATIVE

Normal Operation
The smart junction box (SJB) supplies the control voltage to the horn relay (part of the SJB). When the horn switch (part of the steering wheel) is pressed, the switch closes and ground is applied from the steering wheel switch harness through the clockspring to the horn relay through circuit (BR). The horn relay is then energized, applying voltage to the horn through circuit (Y/R), enabling the horn to sound. Ground for the horn is supplied through circuit (B/G).

Possible Causes
- Fuse
- Wiring, terminals or connectors
- Steering wheel switch harness
- Horn
- Clockspring
- Horn switch (part of the steering wheel)
- SJB

Diagnostic Procedure

CAUTION: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Step 1-Step 4:




Step 5-Step 9:




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