F 150 4WD V8-5.4L Flex Fuel (2008)
Driver/Vehicle Information Display: Pinpoint Tests
Test A: The Message Center Is Not Operating Correctly
PINPOINT TEST A: THE MESSAGE CENTER IS NOT OPERATING CORRECTLY
Normal Operation
The message center display is integrated into the lower RH corner of the instrument cluster (IC). The instrument cluster (IC) odometer, trip odometer,
compass, outside air temperature and message center displays are contained in the same window. The message center switch is hardwired to the
instrument cluster (IC) through circuits 1411 (GY/OG) and 1396 (VT/WH). The message center switches use a different resistance value for each
switch, allowing the instrument cluster (IC) to determine which switch is pressed.
This pinpoint test is intended to diagnose the following:
-
Instrument cluster (IC)
-
Message center switch
A1-A3
Test B: The Message Center Switch Does Not Operate Correctly
PINPOINT TEST B: THE MESSAGE CENTER SWITCH DOES NOT OPERATE CORRECTLY
Normal Operation
The message center functionality is controlled through the message center switch, which is hardwired to the instrument cluster (IC) through the input
circuit 1411 (GY/OG) and the return circuit 1396 (VT/WH). There are 3 message center switch buttons with each button operating a switch that uses
different resistance values. The instrument cluster (IC) sends out a reference voltage to the message center switch on the input circuit and monitors the
voltage drop when a message center switch button is pressed. The voltage drop will vary depending upon the resistance of each button, providing a
specific indication to the instrument cluster (IC) which switch is pressed.
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DTC B1209 (EIC Switch-2 Assembly Circuit Failure) - sets on-demand in the instrument cluster (IC) if any of the buttons on the message center
are stuck or pressed during the self-test.
This pinpoint test is intended to diagnose the following:
-
Wiring, terminals or connectors
-
Instrument cluster (IC)
-
Message center switch
