Last Modified: 11-29-2007 1.6 J
Service Category: Audio/Visual/Telematics Section: Navigation/Multi Info Display
Model Year: 2008 Model: Sequoia Doc ID: RM000001034027X
Title: NAVIGATION / MULTI INFO DISPLAY: NAVIGATION SYSTEM: INSPECTION PROCEDURE (2008 Sequoia)

Noise Occurs

INSPECTION PROCEDURE

PROCEDURE

1.

CHECK SPEAKER INSTALLATION

(a) Check that each speaker is securely installed.

OK:

Each speaker is securely installed.

OK

2.

IDENTIFY NOISE SOURCE

(a) Check the noise condition.

HINT:

The radio has a noise prevention function to reduce noise when listening to the radio. If a loud noise occurs, check whether the ground at the antenna mounting base and the noise prevention unit are installed and wired correctly.

Condition in Which Noise Occurs

Noise Type

Depressing accelerator pedal increases noise, and stopping engine stops noise immediately

Generator noise

When A/C or heater is operating

Blower motor noise
  • When rapidly accelerating on unpaved road
  • When ignition switch is turned ON

Fuel pump noise
  • When horn switch is pressed and released
  • When horn switch is pressed and held down

Horn noise

Running engine causes soft noise, and stopping engine stops noise immediately

Ignition noise

Noise occurs synchronously with turn signal flash

Flasher noise

Noise occurs during window washer operation

Washer noise

Running engine causes noise, but stopping engine does not stop noise

Engine coolant temperature sensor noise

When wiper is operating

Wiper noise

When brake pedal is depressed

Stop light switch noise

Other

Static electricity on vehicle

HINT:

  • In the chart's left column, find the situation that matches the customer's vehicle. Then, in the right column, find the part that is causing the noise. Check the noise filter on the part.
  • To save time and avoid a misdiagnosis, first make sure that the noise is not originating from outside the vehicle.
  • Troubleshoot noise problems in order of loudness, starting with the loudest noise.
  • Setting the radio to a frequency that receives no signal may make recognition of the noise problem easier.

OK:

The noise source can be determined.

OK