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Home >> Mazda >> 2013 >> 5 Grand Touring >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Entertainment Systems >> Symptom Troubleshooting [Radio] >> No.4 Noise From Radio (Fm Only) [Radio] >> Diagnostic Procedure

Diagnostic Procedure

STEP INSPECTION ACTION
1
  • Tune to local broadcasting station and check reception condition.
  • Is reception okay?
 Yes Tune to correct frequency of broadcasting station.
If not preset, preset it.
No Go to the next step.
2
  • Is aftermarket electronic equipment (two-way radio, navigation system, mobile phone, etc.) installed?
 Yes Go to the next step.
No Go to Step 4.
3
  • Remove aftermarket electronic equipment.
  • Turn audio unit ON and check reception condition.
  • Is reception improved?
 Yes The system is normal. (Explain to customers that aftermarket electronic equipment is cause of noise)
No Go to the next step.
4
  • Measure battery voltage.
  • Is battery voltage okay?

    Specification: 

  • With ignition switch ON: 11.5 V or more 
  • At idling: 12.5 V or more 
NOTE:
  • Inspect that battery cables are connected to terminals securely.
 Yes Go to the next step.
No Charge battery. Inspect charging system, and repair or replace if necessary.
5
  • Is noise occurring only when vehicle electrical system (e.g. fuel pump) operates?
NOTE:
  • Identify subject electrical component by disconnecting fuse, turning switch ON & OFF, or disconnecting & connecting connector.
  • It will be easy when simulation function on M-MDS is used.
 Yes Go to the next step.
No Go to Step 7.
6
  • Inspect power supply, ground condition, and noise prevention capacitor for electrical component.
  • Is noise present after inspection?
NOTE:
  • Inspect the following:
    • Power supply to electrical component for voltage drop (compare with battery voltage)
    • Resistance between ground of electrical component and body. (Should be close to 0 ohm)
    • Installation condition of noise prevention capacitor for fuel pump etc.
 Yes Go to the next step.
No Troubleshooting completed.
7
  • Inspect antenna feeder connection condition.
  • Is connection okay?
 Yes Go to the next step.
No Insert antenna feeder securely.
8
  • Switch the ignition OFF (LOCK).
  • Measure continuity between antenna feeder axis and ground.
  • Is there any continuity?
 Yes Replace antenna feeder.
(See ANTENNA FEEDER NO.1 REMOVAL/INSTALLATION .)
(See ANTENNA FEEDER NO.2 REMOVAL/INSTALLATION .)
No Go to the next step.
9
  • Compare reception with other audio unit on same model (model/unit) under same problem conditions.
  • Is reception equivalent between customer's unit and compared unit?
 Yes The system is normal (It is caused by electronic jamming from outside, or inferior broadcasting station signal condition).
No Go to the next step.
10
  • Retighten ground fixation for antenna installation part and antenna amplifier.
  • Is noise present, after retightening?
NOTE:
  • When antenna is not grounded perfectly, FM particular noise is likely to be noticeable.
 Yes Replace audio unit.
(See AUDIO UNIT REMOVAL/INSTALLATION .)
No Troubleshooting completed.
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