2

No
Yes
No

Will CDs play normally within 1
hour of warming and drying?

Go to step 2.
No action required.
No action required.
Replace the CD player.

Table 5, Error Message Diagnostics: "ERR"

Poor Reception Diagnostics
Step

1

2

Test Procedure
Poor reception may be caused by
antenna problems, a defective
radio, or radio frequency noise
injected into the power or antenna
circuits.
Tune the radio to a local station
that exhibits poor reception (static,
background noise, or interference).
Disconnect the antenna coaxial
cable from the back of the radio.
See Fig. 3.

Poor Reception Diagnostics
Test Result
Action
Interference may be caused by indoor lighting. These
diagnostics may need to be performed outside and away
from static sources, such as fluorescent lights and electric
—
power tools.
Go to step 2.
The noise is not caused by the antenna system.
Yes
Go to step 3.

No

Go to step 6.

Is there still noise?

Page 6

Freightliner Service Bulletin, 2/21/20

Radio and Integrated Thin-Film Antenna Troubleshooting,
and Field Service Updates
> FLA COE
> FLB COE
> FLD Conventional
> Business Class
> FLC 112 Conventional

Step

3

4

> Century Class Conventional
> Argosy
> Cargo
> Columbia
> Coronado

Test Procedure
Test for poor ground and power
connections to the radio and cab.
Wiggle the power and ground
connections from the battery
through connection points at the
starter, cab, and frame while
listening for changes in the static
sounds.
Does the static change when any
of the connection points are
wiggled?
Check the voltage drop. Turn off all
accessories and measure the
voltage drop between the battery
and the radio for both the power
and ground circuits.
Is the voltage drop greater than
0.25 VDC for either circuit?

5

Install a known good radio set to
the same station as the one in the
truck.
Is the problem still present?

6

If a substitute antenna is available,
plug it into the radio to determine if
the problem is still present.
Is the problem still present with the
test antenna?

7

8

9

Is the antenna system a multiband
system with a multiplexer box?
With the antenna unplugged from
the radio, measure the resistance
between the antenna cable center
pin and ground. Is the resistance
greater than 10,000 ohms?
Measure resistance between the
center pin and the center
conductor at the base of the
antenna mast.
Is the resistance less than 5 ohms?

Freightliner Service Bulletin, 2/21/20

Freightliner
Service Bulletin

> Business Class M2
> Cascadia
> 108SD/114SD
> New Cascadia

Poor Reception Diagnostics
Test Result

54-148

Action

Yes

Clean and repair the connection. Apply dielectric protection
when the connection is restored.

No

Go to step 4.

Yes

Troubleshoot the wiring for the source of the resistance that
is causing the voltage drop. Repair as appropriate.

No

Go to step 5.

No
Yes
No

The noise source is likely coming from the vehicle power
system. Isolate the problem by disconnecting fuses and/or
circuit breakers one by one until the source of the noise is
isolated. Check the ground circuit to that component and
repair as appropriate.
Replace the radio.
Troubleshoot for interference sourced from other
components or accessories on the vehicle. Isolate the
problem by disconnecting fuses and/or circuit breakers one
by one until the source of the noise is isolated. Check the
ground circuit to that component and repair as appropriate.
Go to step 7.
Continue to Table 7.
Go to step 8.

Yes

Go to step 9

No

The antenna cable is shorted. Locate the short and replace
the necessary cable.

Yes

Go to step 10.

No

Repair a poor or corroded antenna cable connection;
usually at the antenna base, or if the cable shows the
resistance, replace the cable.

Yes

No

Yes

Page 7

54-148
Freightliner
Service Bulletin

Step

10

Radio and Integrated Thin-Film Antenna Troubleshooting,
and Field Service Updates
> FLA COE
> FLB COE
> FLD Conventional
> Business Class
> FLC 112 Conventional

Test Procedure
Measure the resistance between
the antenna cable outer shield from
the radio end of the cable to the
cab ground. Also, measure the
resistance of the antenna cable
shield from the connection at the
radio end to the end at the antenna
end.
Is the resistance less than 5 ohms
for both of these checks?

> Century Class Conventional
> Argosy
> Cargo
> Columbia
> Coronado

Poor Reception Diagnostics
Test Result

> Business Class M2
> Cascadia
> 108SD/114SD
> New Cascadia

Action

Yes

The antenna system is working properly. A possible solution
applicable to some older model vehicles is to consider
installing a RAMI or other multiband antenna system. See
Fig. 4. This option is an upgrade and not covered by
warranty.

No

Repair a poor or corroded antenna cable connection;
usually at the antenna base, or if the cable shows the
resistance, replace the cable.

Table 6, Poor Reception Diagnostics

Page 8

Freightliner Service Bulletin, 2/21/20

Radio and Integrated Thin-Film Antenna Troubleshooting,
and Field Service Updates
> FLA COE
> FLB COE
> FLD Conventional
> Business Class
> FLC 112 Conventional

> Century Class Conventional
> Argosy
> Cargo
> Columbia
> Coronado

> Business Class M2
> Cascadia
> 108SD/114SD
> New Cascadia

54-148
Freightliner
Service Bulletin

1

B

2
1
A

B

07/30/2001

A. Follow air line routing.
1. Antenna Coaxial Cable

f542872a

B. Follow main cab harness routing.
2. Antenna Coaxial Connector
Fig. 3, Antenna Coaxial Cable Routing

Freightliner Service Bulletin, 2/21/20

Page 9

54-148

Radio and Integrated Thin-Film Antenna Troubleshooting,
and Field Service Updates

Freightliner
Service Bulletin

> FLA COE
> FLB COE
> FLD Conventional
> Business Class
> FLC 112 Conventional

> Century Class Conventional
> Argosy
> Cargo
> Columbia
> Coronado

> Business Class M2
> Cascadia
> 108SD/114SD
> New Cascadia

A

1

A

A

09/06/2001

f543394

A. Antenna Cable Connecting Points
1. Multiplexer
Fig. 4, RAMI Antenna Cable Routing

Page 10

Freightliner Service Bulletin, 2/21/20

Radio and Integrated Thin-Film Antenna Troubleshooting,
and Field Service Updates
> FLA COE
> FLB COE
> FLD Conventional
> Business Class
> FLC 112 Conventional

> Century Class Conventional
> Argosy
> Cargo
> Columbia
> Coronado

54-148
Freightliner
Service Bulletin

> Business Class M2
> Cascadia
> 108SD/114SD
> New Cascadia

Antenna Diagnostics
Step

1

Test Procedure
Remove the antenna masts from
their mounting bases. Remove the
cap at the top of the antenna
masts. Inspect the solder joint/
connection at the bottom of the
antenna masts and measure the
resistance of the antenna from
bottom to top. Flex and twist the
mast while making the
measurement.
NOTE: A small cut may be needed
in the shrinkable wrap at the top of
the mast to expose the wire. Use
care that the wire does not come
out of the slot and uncoil. The wire
is coated with a dielectric material.
It can be lightly sanded to expose
the conductor.

2

Does the resistance remain at less
than 5 ohms?
Disconnect all radios from the
multiband splitter box. Measure the
resistance from the bracket to the
center standoff nut.

3

Is the resistance greater than
10,000 ohms?
Measure the resistance from the
bracket to a solid cab ground.

4

Is the resistance less than 5 ohms?
Measure the resistance from the
center standoff nut of each antenna
base to the center conductor at the
multiplexer connector.
Is the resistance of either cable
greater than 5 ohms?

Freightliner Service Bulletin, 2/21/20

Multiband Antenna Diagnostics
Test Result

Action

Yes

Go to step 2.

No

Replace the defective antenna mast.

Yes

Go to step 3.

No

Locate and repair the shorted antenna cable or mount.

Yes

Go to step 4.

No

Repair the poorly grounded antenna mount.

Yes

Replace the damaged antenna cable.

No

Go to step 5.

Page 11

54-148

Radio and Integrated Thin-Film Antenna Troubleshooting,
and Field Service Updates

Freightliner
Service Bulletin

Step

> FLA COE
> FLB COE
> FLD Conventional
> Business Class
> FLC 112 Conventional

Test Procedure
With the multiplexer box
disconnected from all radios and
antennas, measure the resistance
from the following:

> Century Class Conventional
> Argosy
> Cargo
> Columbia
> Coronado

Multiband Antenna Diagnostics
Test Result

> Business Class M2
> Cascadia
> 108SD/114SD
> New Cascadia

Action

Yes

Replace the multiplexer box.

No

Go to step 6.

Yes

The antenna system is performing properly. No further
action is necessary.

No

Replace the multiplexer box.

• Each antenna cable center
conductor to the AM/FM
radio cable center