Land Rover Discovery: Diagnosis and Testing Speakers
PRINCIPLES OF OPERATION
For a detailed description and operation of the information and
entertainment system, refer to the relevant description and operation
section of the workshop manual.
INSPECTION AND VERIFICATION
CAUTION:
Diagnosis by substitution from a donor vehicle is NOT acceptable.
Substitution of control modules does not guarantee confirmation of a
fault and may also cause additional faults in the vehicle being
checked and/or the donor vehicle.
NOTES:
- Verify the customer concern
- Visually inspect for obvious signs of damage and system integrity
Visual Inspection
- If an obvious cause for an observed or reported concern is found,
correct the cause (if possible) before proceeding to the next step
- If the cause is not visually evident, verify the symptom and refer to
the
Symptom Chart, alternatively check for Diagnostic Trouble Codes
(DTCs) and refer to the DTC Index
- Check DDW for open campaigns. Refer to the corresponding bulletins
and SSMs which may be valid for the specific customer complaint and
carry out the recommendations as required
SPEAKER DIAGNOSTICS
The symptom chart below should be used when diagnosing speaker faults
and must be worked through prior to replacing any speakers
REPORTED
SYMPTOM:
Speaker
Buzz
SYMPTOM
DESCRIPTION:
- Periodic
high
frequency
sound
(sounds like
an insect
buzzing)
POTENTIAL CAUSES
(FOR GUIDANCE
ONLY):
- Resonance in a trim
component, e.g. NVH
(noise, vibration and
harshness) insulating
cloth against speaker
grill mesh
- Lack of retention of
interior and exterior
trim panels
- Loose harness/harness
clips
- Labels vibrating
against trim/nearby
components
- Nearby modules vibrating against
trim/BIW
- Mechanical failure of
internal speaker
component
REPORTED
SYMPTOM:
Speaker
Rattle
SYMPTOM
DESCRIPTION:
- Sounds like
loose
components
rattling
around in /
near the
speaker
POTENTIAL CAUSES
(FOR GUIDANCE
ONLY):
- Loose trim
- Loose items in or
around speaker
- Loose fixings
- Debris inside speaker
- Loose harness
REPORTED
SYMPTOM:
Speaker
Hiss /
Static
SYMPTOM
DESCRIPTION:
- Wideband
noise (White
Noise) /
interference
(such as
experienced
from a
poorly tuned
radio signal)
POTENTIAL CAUSES
(FOR GUIDANCE
ONLY):
- Loose connection at
speaker
- Loose connection at
amplifier
- Loose connection at
audio head unit
- Non JLR-approved
equipment installed
(e.g. USB cables)
- Damage to harness
connected to the
speaker
- Audio amplifier fault
- Audio head unit fault
REPORTED
SYMPTOM:
Speaker
Crackle
SYMPTOM
DESCRIPTION:
- Electrical
crackling
noise (such
as from a
loose
electrical
connection)
- A rapid
succession
of short
sharp noises
- Electrical
interference
POTENTIAL CAUSES
(FOR GUIDANCE
ONLY):
- Loose connection at
speaker
- Loose connection at
amplifier
- Loose connection at
audio head unit
- Non JLR-approved
equipment installed
(e.g. USB cables)
- Damage to harness
connected to the
speaker
- Audio amplifier fault
- Audio head unit fault
- Internal electrical issue
in speaker
REPORTED
SYMPTOM:
Speaker
Distorted
SYMPTOM
DESCRIPTION:
- No
significant
extraneous
noise, but
audio
reproduction
is not as
expected
e.g. is not
clean
sounding
POTENTIAL CAUSES
(FOR GUIDANCE
ONLY):
- Loose trim
- Non JLR-approved
equipment installed
(e.g. USB cables)
- Resonance in a trim
component, e.g. NVH
(noise, vibration and
harshness) insulating
cloth against speaker
grill mesh
- Lack of retention of
interior and exterior
trim panels, nearby
harnesses/components
- Mechanical failure of
internal speaker
component
RECOMMENDED ACTION
- Replicate fault and
confirm audio source(s)
affected:
DAB/CD/Bluetooth via
phone/USB via
phone/USB via
iPod/AM/FM radio
- If fault is specific to one
source, audio source must
be investigated further as
a speaker failure in this
instance is less likely, e.g.
if issue is only seen on
DAB, check DAB module
is fully functioning
correctly and software is
up to date
- Confirm if issue is heard
on stereo and/or surround
sound settings
- Isolate the customer
symptom to specific
vehicle area using balance
and fade audio settings.
Check for any loose
objects in the area, e.g.
pens, keys, coins, etc
- Check for any previous
work carried out in this
area by referring to DDW
to help in diagnosing the
issue
- Check SDD/Topix for
any audio related
SSM/TSB and software
updates. Carry out service
updates as required.
Retest to confirm if issue
is resolved
- Apply pressure by hand
to door/trim panel and
nearby modules (i.e.
switchpacks) to confirm if
there is a change in
symptom sound
- If issue is still present,
or condition changes by
applying pressure to the
trim, remove internal trim
and apply gentle pressure
to components within the
door to see if sound
changes. This will also
allow access to relevant
speaker
- If symptom condition is
unchanged by applying
pressure to the trim,
examine trim to find
source of audio issue and
fix as appropriate using
Squeaks and Rattle kit
LTB00389. If audio issue is
still present then move to
step 10
- Check around front
face of speaker for any loose items that may be
touching the speaker, e.g.
debris, loose fixings, etc
- Check all speaker
fixing screws are secure
and correctly torqued,
refer to workshop manual
for correct torque figures
- Check harness
assembly is not vibrating
against speaker unit or
nearby trim/components
and that it is clipped and
routed correctly
- Check harness
assembly is not trapped
or impeding the speaker
unit and rectify as
required
- Check harness
assembly connections are
fully inserted and secured
to speaker and amplifier.
Also check harnesses are
securely connected to
nearby components
- Check for harness
damage and
repair/replace as required
- If a gasket is present
on speaker, without
removing the speaker
visually check it is
correctly seated against
speaker surface and not
noticeably damaged
- If audio issue is still
present, remove speaker
from mountings, retest
speaker in hand to see if
the fault is still present
- Check for debris in
speaker and remove.
Retest speaker in hand
- Check for damage to
speaker and replace
speaker if damage is
present
- Connect new speaker
to harness, check new
speaker in hand to ensure
fault has been rectified. If
issue has been resolved,
reassemble trim with new
trim retention clips
- Check if audio issue is
still present. If issue has
been resolved,
reassemble trim and
retest. If issue is still
present, contact JLR
Dealer Technical Support
following the guidelines in
the policy and procedures
manual
PINPOINT TESTS FOR SUSPECTED SPEAKER FAULTS
NOTE:
See separate Pinpoint Tests (below) for sub-woofer faults
Pinpoint Tests For Suspected Sub-Woofer Faults
NOTE:
See separate Pinpoint Tests (above) for other speaker faults
DTC INDEX
For a list of Diagnostic Trouble Codes (DTCs) that could be logged on this
vehicle, please refer to Section 100-00.
READ NEXT:
The complexities of the electronics involved with the telematics system, of
which the GPS antenna and navigation display are parts, and the
multiplexed communication network which are connected to it
REMOVAL
NOTES:
Removal steps in this procedure may contain installation details.
RH illustration shown, LH is similar.
Refer to: Front Door Trim Panel (501-05 Interior Trim and
Ornamentation, Remo
ACTIVATION
NOTES:
The following must be adhered to when updating the software level
of the InControl Touch Audio Head Unit (AHU).
When attempting to update the software level on the InControl
Tou
SEE MORE:
REMOVAL
CAUTION:
Do not allow the side air curtain module to twist. Failure to follow
this
instruction may result in damage to the component.
NOTES:
Removal steps in this procedure may contain installation details.
Right illustration shown, left is similar.
All vehicles
Disconnect the battery g
PRINCIPLES OF OPERATION
For a detailed description of the Locks, Latches and Entry Systems, refer to
the relevant Description and Operation section in the workshop manual.
REFER to: Handles, Locks, Latches and Entry Systems (501-14 Handles,
Locks, Latches and Entry Systems, Description and Operatio