I have a 2500 with 900 miles on it and the dimmer light that lets you know the lights are on bright will flash when the lights are on or off and its very annoying at night. I took it by the dealer and i told them that the flash is very dim and they would not be able to see it during the daytime. I picked it up and they daid that they could not find anything wrong and could not fix it cause they didnt find anyting wrong. I asked them what was i suppose to do and the lady in service hinted to me to get a second opinion on it. Im tired of fooling with these people i know what it does and i told them they would not see it during the daytime! What can i do to get this thing fixed? Has anyone else had the dimmer light flash with them?

 

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That is classic dealer service.

The lights on the instrument cluster are LEDs and they are soldered to the board. It kinda sounds like you have a bad instrument cluster but you could also be getting a bad signal from the light control module.

Have you tried messing with the multifunction control switch to see if that will stop the annoying flash? The multi control sw is the turn signal switch. Try pulling/pushing the lever to see if that changes anything.

Try the Insturment Cluster Self Test (from the 2004 shop manual and to summarize, hold down the trip odometer button and then turn the ignition switch to on, release odometer button, watch the light show!):

The instrument cluster actuator test will put the
instrument cluster into its self-diagnostic mode. In
this mode the instrument cluster can perform a selfdiagnostic
test that will confirm that the instrument
cluster circuitry, the gauges, and the indicators are
capable of operating as designed. During the actuator
test the instrument cluster circuitry will position
each of the gauge needles at various calibration
points, illuminate all of the segments in the Vacuum
Fluorescent Display (VFD) units, turn all of the indicators
on and off again, display any Diagnostic Trouble
Code (DTC) information, and display the number
of ignition key cycles that have occurred since the
DTC was detected. It is suggested that a note pad
and pencil be used to write down any fault information
that is displayed during the test for reference.
Successful completion of the actuator test will confirm
that the instrument cluster is operational. However,
there may still be a problem with the PCI data
bus, the Powertrain Control Module (PCM), the
Engine Control Module (ECM), the Front Control
Module (FCM), the Transmission Control Module
(TCM), the Transfer Case Control Module (TCCM),
the Airbag Control Module (ACM), the Controller
Anti-lock Brake (CAB), or the inputs to one of these
electronic control modules. Use a DRBIIIt scan tool
to diagnose these components. Refer to the appropriate
diagnostic information.
(1) Begin the test with the ignition switch in the
Off position.
(2) Depress the odometer/trip odometer switch button.
(3) While still holding the odometer/trip odometer
switch button depressed, turn the ignition switch to
the On position, but do not start the engine.
(4) Release the odometer/trip odometer switch button.
(5) The instrument cluster will simultaneously
illuminate all of the operational segments in both
VFD units, perform a bulb check of each operational
LED indicator. The VFD segments and LED indicators
remain illuminated as each gauge needle is
swept to several calibration points and back. If a
VFD segment or an LED indicator fails to illuminate,
or if a gauge needle fails to sweep through the calibration
points and back during this test, the instrument
cluster must be replaced. Following these tests,
the actuator test will proceed as described in Step 6.
(6) The text “C Code” is displayed in the odometer
VFD for about three seconds. If there is no stored
fault information, the display will show two pairs of
zeroes in the format “00” “00”, which indicate that
the display of fault information is done. If there is
stored fault information, two sets of two-digit alpha
and alpha-numeric fault codes will appear in the
odometer display for a three second interval. The
first pair of digits represents a Diagnostic Trouble
Code (DTC), or fault code for the instrument cluster.
The second pair of digits is a counter for the number
of ignition key cycles that have occurred since the
displayed DTC was set. The instrument cluster will
continue to display additional sets of two pairs of digits
at three second intervals until all of the stored
codes have been displayed, which is again signaled
by a code of “00” “00”.