Inspection Procedure 6

Noise Appears at Certain Places When Traveling (AM).

DIAGNOSIS

STEP 1. Check whether the noise occurs when entering or near a particular structure (building, tunnel, mountain, etc.).

Q: Dose the noise occur when entering or near a particular structure (building, tunnel, mountain, etc.)?

YES: Go to Step 3.

NO: Go to Step 2.

STEP 2. After taking the following measures to prevent the noise, check that no noise appears.

1. Change to a different station with a stronger signal.
2. Suppress high tones to reduce noise.
3. Extend antenna completely.

Q: Do the above measures eliminate the noise?

YES: The above causes should be considered.

NO: Go to Step 4.

STEP 3. Ask the owner about the state of the noise.

1. Find out the following information from the owner.
2. Place where the noise occurs.
3. Locality conditions (valley, mountain, etc.).
4. Name and frequency of stations affected by noise.

Q: Is the noise a vehicle noise or an external noise?

Vehicle noise: It may not be possible to prevent noise if the signal is weak.

External noise: In almost all cases, prevention on the receiver side is impossible. Weak signals especially are susceptible to interference. Go to Step 4.

STEP 4. Check that there is no noise.

Q: Does noise still exist?

YES: If there is more noise than on radios in other vehicles, find out the noise condition and the name and frequency of the receiving stations from the owner, and consult with the radio manufacturer's service center.

NO: Normal.