Diagnosis

The customer should be interviewed to verify the symptoms and the conditions under which they occur (location, station, etc.). Then, perform the appropriate diagnosis based on the symptom.

NOTE:
The information in this Service Bulletin applies to Prelude and Accord models. Only the Accord model is illustrated; however, the Prelude is similar.

Diagnosis 1. Poor Reception

1. Turn the ignition switch ON; then, turn the radio on to extend the antenna mast.





2. Measure the resistance between the top section and the bottom section of the antenna mast.

If the resistance is more than 10 ohms, go to CORRECTIVE ACTION, Antenna Mast Replacement.

If the resistance is less than 10 ohms, continue with step 3.

3. Disconnect the coaxial cable from the antenna jack.





4. Measure the resistance between the top section of the antenna and the center pin of the antenna jack.

^ If the resistance is less than 10 ohms, go to Coaxial Cable Test.

^ If the resistance is more than 10 ohms, continue with step 5.





5. Remove the antenna mast nut with the special tool; then, remove the antenna mast.





6. Measure the resistance between the center pin of the antenna jack and the threaded portion of the antenna tube.

^ If the resistance is less than 10 ohms, go to CORRECTIVE ACTION, Antenna Mast Replacement.

^ If the resistance is more than 10 ohms, go to CORRECTIVE ACTION, Antenna Tube Replacement.

Diagnosis 2. Electrical Noise or Interference

1. Disconnect the coaxial cable from the antenna jack.





2. Measure the resistance between the antenna collar and body ground.

^ It the resistance is more than 1 ohm, go to CORRECTIVE ACTION, Antenna Collar Replacement.

^ If the resistance is less than 1 ohm, continue with step 3.





3. Measure the resistance between the antenna tube and the outside contact of the antenna jack.

^ If the resistance is more than 1 ohm, go to CORRECTIVE ACTION, Antenna Tube Replacement.

^ If the resistance is less than 1 ohm, continue with Coaxial Cable Test.

Coaxial Cable Test

1. Test drive the car to verify the customer's description of the symptom.

^ If the symptom cannot be reproduced, contact the customer for more information regarding the symptom.

^ If the symptom can be reproduced, continue with step 2.

2. Disconnect the coaxial cable from the antenna and the radio.





3. Substitute a new coaxial cable. Connect the new coaxial cable to the antenna; then, run the cable on the outside of the car and connect it to the radio.

4. Test the radio.

^ If the symptom has gone away, install the new coaxial cable.

^ If the symptom persists, continue troubleshooting the audio system.