System Performance Check - Noise Or Poor Reception

System Performance Check - Noise Or Poor Reception:

IMPORTANT:
^ The purpose of the System Performance Check is to distinguish between noise or poor reception. Some noises induced into the system may not be audible, but can cause poor reception. All reception and noise listening should be done outside, away from electrical interference (power lines, buildings, etc.). The hood should also be closed.
^ Radio frequency interference (RFI) can cause a fewer number of stations to be received in one of the three modes. The RFI can be caused by various vehicle components. This may be the cause of the difference in reception. Check for components powered up in the three various key positions. This may eliminate engine running components, ignition on components, etc. For example, if the same number of stations are received with the engine running as when the engine was off, the components active with the engine running are not causing the interference. Refer to "RFI Questionnaire and Diagnosis". RFI - Radio Frequency Interference Chart 21 - RFI Diagnostics