Operation; Diagnosis And Testing - Antenna Body And Cable - Chrysler 2005 Crossfire SRT6 Service Manual

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OPERATION

The antenna body and cable connects the antenna
mast to the radio. The radio antenna is an electromag-
netic circuit component used to capture radio fre-
quency signals that are broadcast by local commercial
radio stations in both the Amplitude Modulating (AM)
and Frequency Modulating (FM) frequency ranges.
These electromagnetic radio frequency signals induce
small electrical modulations into the antenna as they
move past the mast. The antenna body transfers the
weak electromagnetic radio waves induced into the
rigid antenna mast into the center conductor of the
flexible primary antenna coaxial cable. The braided
outer shield of the antenna coaxial cable is grounded
through both the antenna body and the radio chassis,
effectively shielding the radio waves as they are con-
ducted to the radio. The radio then tunes and ampli-
fies the weak radio signals into stronger electrical
signals in order to operate the audio system speakers.

DIAGNOSIS AND TESTING - ANTENNA BODY AND CABLE

The following four tests are used to diagnose the antenna with an ohmmeter:
• Test 1 - Coax cable at back of radio to ground test
• Test 2 - Tip-of-mast to tip-of-conductor test
• Test 3 - Body ground to battery ground test
• Test 4 - Body ground to antenna coaxial cable shield test.
WARNING: DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, SIDE AIRBAG, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE, THEN WAIT TWO MIN-
UTES FOR THE AIRBAG SYSTEM CAPACITOR TO DISCHARGE BEFORE PERFORMING FURTHER DIAGNO-
SIS OR SERVICE. THIS IS THE ONLY SURE WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO TAKE
THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
The ohmmeter test lead connections for each test are shown in the illustration.
TEST 1
Test 1 checks the antenna conductor components for
a short circuit. This test should be performed first on
the entire antenna circuit, from the antenna mast to
the center conductor of the coaxial cable connector at
the radio. If a short circuit is detected, each of the
three antenna conductor components (antenna mast,
antenna body and cable) should be isolated and
tested individually to locate the exact component that
is the source of the short circuit. To begin this test,
proceed as follows:
1. Turn the ignition off.
2. Disconnect the antenna cable coaxial connector
from the back of the radio.
3. Touch one ohmmeter test lead to the shield ground
of the coaxial cable. Touch the other test lead to the center conductor pin of the antenna cable coaxial connector
for the radio. Check the ohmmeter reading for continuity.
AUDIO - SERVICE INFORMATION 8A - 29