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Horns Inoperative

WARNING: This page is about a different car, the 2004 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.
Horns Inoperative

Step Action Yes No
Schematic Reference: Horns Schematics 
1 Did you review the Horn System Description and Operation and perform the necessary inspections? Go to Step 2  Go to Symptoms - Horns 
2
  1. Remove the horn relay.
  2. Using a test lamp, test for battery positive voltage at the switch side of the relay battery positive voltage circuit. Refer toCircuit Testing in Wiring Systems.
Is voltage present?		 Go to Step 3  Go to Step 4 
3 Using a test lamp, test for battery positive voltage at the coil side of the relay battery positive voltage circuit. Refer toCircuit Testing in Wiring Systems.
Is voltage present?		 Go to Step 5  Go to Step 4 
4 Repair the open or short in the battery positive circuit. Refer toCircuit Testing in Wiring Systems.
Did you find and correct the condition?		 Go to Step 18  -
5
  1. With the horn switch depressed.
  2. Using a test lamp connected to battery positive voltage. Test the horn signal circuit at the relay for ground. Refer toCircuit Testing in Wiring Systems.
Is ground present?		 Go to Step 7  Go to Step 6 
6
  1. With the horn switch depressed.
  2. Using a test lamp connected to battery positive voltage. Test the horn signal circuit at the switch for ground. Refer toCircuit Testing in Wiring Systems.
Is ground present?		 Go to Step 7  Go to Step 12 
7
  1. Disconnect the horn connector.
  2. With the horn switch depressed, Use a test lamp connected to a good ground, Test the horn voltage feed circuit at the horn connector for battery positive voltage. Refer toCircuit Testing in Wiring Systems.
Is voltage present?		 Go to Step 9  Go to Step 15 
8
IMPORTANT: The horn switch circuit is part of the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement in SIR.
To disable the SIR system refer to SIR Disabling and Enabling Zone 3 in SIR.Repair the open in the horn switch signal circuit. Refer toCircuit Testing in Wiring Systems.Did you find and complete the repair?		 Go to Step 18  -
9 With the horn connector still disconnected, test the ground circuit for ground. Refer toCircuit Testing in Wiring Systems.
Is there ground present?		 Go to Step 10  Go to Step 11 
10 Replace the horn. Refer to Horn Replacement .
Did you complete the replacement?		 Go to Step 18  -
11 Repair the open in the horn ground circuit. Refer to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 18  -
12 Using a test lamp connected to battery positive voltage, test the horn switch ground circuit for ground. Refer toCircuit Testing in Wiring Systems.
Is ground present?		 Go to Step 13  Go to Step 14 
13 Replace the horn switch.
Did you complete the replacement?		 Go to Step 18  -
14 Repair the open in the horn switch ground circuit. Refer to Wiring Repairs in Wiring Systems.
Did you correct the condition?		 Go to Step 18  -
15 With the horn switch depressed, test the horn feed circuit at the relay for battery positive voltage. Refer to Circuit Testing in Wiring Systems
Is voltage present?		 Go to Step 16  Go to Step 17 
16 Repair the open in the horn supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?		 Go to Step 18  -
17 Replace the horn relay.
Did you complete the replacement?		 Go to Step 18  -
18 Operate the system in order to verify repair.
Did you correct the condition?		 System OK Go to Step 2 
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