Toyota Tundra. Manual — part 527

BASIC INSPECTION RESULT CHART

B: Go to step 6

A: Go to Next Step

4. CHECK FOR DTC

a. Check for DTCs and note any codes that are output (see DTC CHECK/CLEAR ).

b. Clear for DTC.

c. Recheck for DTCs. Based on the DTC output in the first step, try to force output of the navigation

system DTC by simulating the operation indicated by the DTC.

HINT:



If the system cannot enter the diagnosis mode, inspect each AVC-LAN communication
signal and repair or replace problem parts.



Even if the malfunction symptom is not confirmed, check for DTCs. This is because the
system stores past DTCs.



Refer to the detailed description on the diagnostic screen, as necessary (see DIAGNOSIS
DISPLAY DETAILED DESCRIPTION ).



Check and clear past diagnostic trouble codes. Check the diagnostic trouble code and inspect
the area the code indicates.

Result

DTC RESULT CHART

B: Go to step 7

A: Go to Next Step

5. PROBLEM SYMPTOMS TABLE

Result

PROBLEM SYMPTOMS RESULT CHART

Result

Proceed to

Display appears

A

Display does not appear

B

Result

Proceed to

DTC does not reoccur

A

DTC reoccurs

B

Result

Proceed to

Fault is not listed in problem symptoms table

A

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Navigation - Tundra

B: Go to step 7

A: Go to Next Step

6. OVERALL ANALYSIS AND TROUBLESHOOTING

a. Terminals of ECU (see TERMINALS OF ECU ).

b. Inspect the steering pad switch (see INSPECTION ).

c. Inspect the front No. 1 speaker (see INSPECTION ).

d. Inspect the front No. 2 speaker (see INSPECTION ).

e. Inspect the front No. 3 speaker (see INSPECTION ).

f. Inspect the front No. 4 speaker (see INSPECTION ).

g. Inspect the rear No. 1 speaker (see INSPECTION ).

h. Inspect the rear No. 2 speaker (see INSPECTION ).

i. Inspect the box speaker (see INSPECTION ).

7. ADJUST, REPAIR OR REPLACE

NEXT: END

IDENTIFICATION OF NOISE SOURCE

1. RADIO WAVE BAND

a. Radio frequency band

1. Radio broadcasts use the radio frequency bands shown in the table below.

Fig. 231: Frequency Reference Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2. SERVICE AREA

a. The broadcast range for AM and FM is very different. Sometimes an AM broadcast can be received

very clearly but FM stereo cannot. FM stereo has the smallest service area, and is prone to picking

Fault is listed in problem symptoms table

B

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2009 ACCESSORIES AND EQUIPMENT Navigation - Tundra

up static and other types of interference (for example, noise).

Fig. 232: Identifying Service Areas Of AM And FM Broadcasts
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

3. RECEPTION PROBLEMS

HINT:

Besides the problem of static, there are other problems, such as "phasing", "multipath" and "fade out".
These problems are caused by the nature of the radio waves themselves, not by electrical noise.

a. AM broadcasts are susceptible to electrical interference called phasing. Occurring only at night,

phasing is the interference created when a vehicle receives 2 radio wave signals from the same
transmitter. One signal is reflected off of the ionosphere and the other signal is received directly
from the transmitter.

Fig. 233: Identifying Phasing
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

b. Multipath is a type of interference created when a vehicle receives 2 radio wave signals from the

same transmitter. One signal is reflected off of buildings or mountains and the other signal is
received directly from the transmitter.

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Navigation - Tundra

Fig. 234: Identifying Multipath
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

c. Fade out is caused by objects (buildings, mountains, etc.) that deflect away part of a signal,

resulting in a weaker signal when the object is between the transmitter and vehicle. High frequency
radio waves, such as FM broadcasts, are easily deflected by obstructions. Low frequency radio
waves, such as AM broadcasts, are much more difficult to deflect.

Fig. 235: Identifying Fade-Out
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

4. NOISE PROBLEMS

a. Technicians must have a clear understanding about the noise problems of the customer's vehicle.

Use the following table to diagnose the problems.

NOISE PROBLEMS CHART

Radio

Wave

Condition in Which Noise

Occurs

Presumable Cause

AM

Noise occurs in a specific area Strong possibility of foreign noise

AM

Noise occurs when
broadcasting is faint



Same program may be broadcasted from various
local stations



If the program is the same, one of those may be
tuned in

AM

Noise occurs only at night

Strong possibility of beats from distant broadcasting

FM

Noise occurs at a specific
place during driving

Strong possibility of multipath noise and fading noise
caused by changes of FM frequency

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Navigation - Tundra