Operation CHARM: Car repair manuals for everyone.

Horn Relay: Testing and Inspection











1. Measure resistance between relay terminal 85 and all other terminals. If any resistance is 5 ohms or less, replace relay. Otherwise, continue with test.






2. Use jumper wires to apply battery voltage to terminals 30 and 85. Measure voltage at terminal 87A. If the voltage is less than 10 volts, replace the relay. Otherwise, continue with test,






3. Use a jumper wire to apply ground to terminal 86. Measure the voltage at terminal 87. If the voltage is less than 10 volts, replace the relay. Otherwise, return to Pinpoint tests. Pinpoint Tests