Hummer H1 (2006+). Manual — part 361

12-120

Electrical System

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NO SOUND FROM ONE SPEAKER (STANDARD)

NO SOUND FROM ONE SPEAKER (MONSOON) (FIGURE 12-87)

4

Check for poor connection at
radio.

Go to step 5

5

Verify the radio is programmed
with the Tech 2. If OK, service
radio.

CHART #2

ACTION

VALUE(S)

YES

NO

1

Ignition switch “off”.

Disconnect radio connectors.

With a DVOM, measure resistance at the
radio connector between speaker + and -
circuits (see schematics).

Approxi-
mately
4 ohms.

Go to step 3.

Go to step 2.

2

With a DVOM, measure the resis-
tance at the speaker connection
from terminal “A” to terminal “B”.

Approxi-
mately
4 ohms.

Repair open or short circuit

in speaker + and - circuits.

Replace speaker.

3

With a DVOM measure the resis-
tance at the radio connector of the
speaker + and - circuits to ground.

Infinite
resis-
tance.

Go to step 4.

Repair short to ground in

speaker + or - circuit.

4

Check for poor connections at
radio or speaker.
If OK, service radio.

CHART #3

STEP

ACTION

VALUE(S)

YES

NO

1

Turn ignition switch to run.
Turn radio on.
Insert cassette or compact disc from
Audio system Diagnostic Kit
J–39916-A.
Set radio balance and fade controls to the
detent (center) position.
Set volume at normal listening level.
While playing the combination test tone
from cassette or compact disc, use a
DVOM, to back probe the speaker con-
nector between terminals “A” and “B”.
Is the voltage greater than 0V AC?

> 0V AC

Go to step 2.

Go to step 3.

CHART #1 (Cont’d)

STEP

ACTION

VALUE(S)

YES

NO

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Electrical System 12-121

2

Check for a poor connection at the inop-
erative speaker.
If OK, replace the speaker.
Is the repair complete?

System OK.

3

Check the + and - speaker circuits for a
short to B+ or ground between the
speaker and amplifier.
Is there a short?

Repair short to ground or

B+.

Go to step 4.

4

Turn ignition switch off.
Disconnect amplifier connector.
Using a DVOM, set to measure resis-
tance, probe the amplifier connector
between the + and - speaker circuits of
the inoperative speaker (see schematics).
Is the resistance approximately 2-4
ohms?

2-4 ohms

Go to step 6.

Go to step 5.

5

Using a DVOM, check the resistance at
the speaker connection between termi-
nals “A” and “B”.
Is the resistance 2-4 ohms?

2-4 ohms

Repair open in speaker +

or - circuit between

speaker connection and

amplifier connection.

Replace speaker.

6

Check for poor connection at amplifier
connector.
Is connection OK?

Replace amplifier.

Repair connection.

CHART #3 (Cont’d)

STEP

ACTION

VALUE(S)

YES

NO

12-122

Electrical System

______________________________________________________

NO SOUND FROM ANY SPEAKER, RADIO DISPLAY OPERATES NORMALLY (MONSOON)
(FIGURE 12-87)

CHART #4

STEP

ACTION

VALUE(S)

YES

NO

1

Disconnect amplifier connector.
Turn ignition switch to run.
Turn radio on.
Insert cassette or compact disc from ƒAudio
System Diagnostic Kit J–39916-A.
Set radio balance and fade controls to the
detent (center) position.
Set radio volume at normal listening level.
While playing the combination test tone
from the cassette or compact disc, use a
DVOM to measure AC voltage between
amplifier connector terminals “E6” and
“E7”.
Is the voltage greater than 0V AC?

> 0V AC

Go to step 2.

Go to step 4.

2

Check for a poor connection at the ampli-
fier connector terminals “E6” and “E7”.
Was poor connection found?

Repair connection.

Go to step 3.

3

Using a DVOM, check for B+ between cir-
cuits 829 and 59 at the amplifier connec-
tion.

Battery +

Replace amplifier.

Repair open or poor con-

nection in circuits 829 and

59.

4

Turn ignition switch to run.
Turn radio on.
Insert cassette or compact disc from the
Audio System Diagnostic Kit J–39916-A.
Set radio balance and fade controls to the
detent (center) position.
Set radio volume at normal listening level.
While playing the combination test tone
from the cassette or compact disc, use a
DVOM and back probe radio connector
between terminals “16” and “15”.
Is the voltage greater than 0V AC?

> 0V AC

Go to step 5.

Go to step 6.

5

Repair open or short in circuit 821 or 820
between radio and amplifier.
Is the repair complete?

System OK.

6

Check for bad connection at radio connec-
tor 16 or 15.
Is bad connection found?

Repair connection.

Replace radio.

7

Check for a short to B+ or ground in circuit
821 between radio and amplifier.
Check for a poor connection at radio con-
nector terminal “16”.
If OK, replace radio.
Is the repair complete?

System OK.

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Electrical System 12-123

ANTENNA SYSTEM TEST

REAR SEAT AUDIO (RSA) DOES NOT OPERATE

CHART #5

STEP

ACTION

VALUE(S)

YES

NO

1

Disconnect negative battery cable.
Disconnect antenna lead-in cable at the
radio receiver.
With a DVOM, measure resistance
between the coax (outer conductor) con-
nector and the negative battery cable.

NOTE: To avoid misdiagnosis be sure
to zero the meter before taking measure-
ments.

Is resistance value greater than.15 ohms?

>.15 ohms

Check the base of the

antenna for a good connec-

tion to body ground.

Check the coaxial cable

interconnects for a poor
connection or corrosion.

Check the ground connec-

tion from the battery nega-

tive cable to the body.

Repair the antenna ground

circuit as necessary.

Go to step 2.

2

Grasp the antenna mast.

While observing the DVOM, wiggle the

antenna and the lead-in cable ground

strap. Does the meter indicate intermit-

tent continuity?

Check the lead-in cable
ground strap for a good

connection to body ground.

Check the coaxial cable
interconnects for a poor

connection or corrosion.

Check the ground connec-

tion from the battery nega-

tive cable to the body.

Repair the antenna ground

circuit as necessary.

Go to step 3.

3

With a DVOM, measure the resistance

between the radio coax lead-in connector

(center conductor) and the antenna mast.

NOTE: To avoid misdiagnosis be sure
to zero the meter before taking measure-
ments.

Does the measured resistance equal ap-
proximately the value listed?

Less than

3.5 ohms

Go to step 4.

Check the coaxial cable
interconnects for a poor

connection or corrosion.

Repair/replace the antenna

coaxial circuit as neces-

sary.

4

While observing the DVOM, wiggle the

antenna. Does the meter indicate inter-

mittent continuity?

Check the coaxial cable

interconnects for a poor
connection or corrosion.

Repair/replace the antenna

coaxial circuit as neces-

sary.

See troubleshooting hints

for noise and poor recep-

tion.

CHART #6

STEP

ACTION

VALUE(S)

YES

NO

1

With ignition on, check for voltage at
RSA pin A8 (RSA ignition signal). Is
voltage present?

Approxi-

mate battery

voltage.

Go to step 2.

Check/repair open circuit
between RSA pin A8 and

radio pin A6.