Circuit Description
The Navigation Display Module determines a majority of diagnostic failures.
The Navigation Display Module sends the Navigation Data Processor a Diagnostic
Memory Report when running through System Inspection Mode. This information
includes Diagnostic Trouble Codes stored in a log by the Navigation Display
Module. These failures occurred during normal operation and were reported
to the Navigation Display Module for storage in this log.
Conditions for Running the DTC
Navigation Display Module is running through System Inspection Mode.
Conditions for Setting the DTC
| • | Back Light abnormality. |
| • | Back Light Heater abnormality. |
| • | Back Light Power Source abnormality. |
| • | Switch Scanning abnormality. |
| • | Back Up Memory abnormality. |
| • | TV Power Source Voltage abnormality. |
| • | Internal Communication Error. |
| • | Chip Bus Request line shorted to ground. |
| • | Synchronous Signal abnormality. |
Action Taken When the DTC Sets
| • | Display will black out if DTC was set due to a Back Light abnormality
or a Back Light Power Source abnormality. |
| • | Display appearance will change if DTC was set due to a Back Light
Heater abnormality. |
| • | Non selected switch will remain active if DTC was set due to an
LED Failure. |
| • | Unable to activate both hard and soft keys if DTC was set due
to a Switch Scanning abnormality. |
| • | Back up contents will change if DTC was set due to a Back Up Memory
abnormality. |
| • | TV Tuner will malfunction if DTC was set due to a RAM abnormality. |
| • | Unable to tune if DTC was set due to a TV Power Source Voltage
abnormality. |
| • | Internal Communication Error appears on the display if DTC was
set due to an Internal Communication Error. |
| • | Slow operation if DTC was set due to the Chip Bus Request line
shorted to ground. |
| • | Blacked out display if DTC was set due to a Synchronous Signal
abnormality. |
| • | This failure will have no effect outside the Navigation System. |
Conditions for Clearing the MIL/DTC
| • | A current DTC will clear when the Navigation Display Module does
not detect the failure during the last execution of the System Inspection
Mode. |
| • | A history DTC will clear using a scan tool. |
Diagnostic Aids
| • | An intermittent may be caused by the following: |
| - | Rubbed through wire insulation |
| - | Broken wire inside the insulation |
| • | Cycle the Ignition Switch even after a successful inspection with
a scan tool so initialization will occur. |
| • | DTC B2468 will not set if DTC B1328, DTC B1327, or DTC U2150 is
current. |
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
-
Determines if the malfunction is present.
-
Determines if the malfunction
is due to an internal fault in the Navigation Display Module or a short to
ground condition in circuit 1692.
Step
| Action
| Value(s)
| Yes
| No
|
1
| Was the Navigation Diagnostic System Check
performed
| --
|
Go to Step 2
| Go to
Diagnostic System Check - Navigation System
|
2
|
- Disconnect the Navigation Data Processor connector C1.
- Disconnect the Navigation Display Module connector C2.
- Measure the resistance between cavity 1 of the Navigation Data
Processor harness connector C1 and ground with a DMM.
Is the resistance measured within the specified range?
| infinite
|
Go to Step 3
|
Go to Step 4
|
3
| Replace the Navigation Display
Module. Refer to
Navigation Display Module Replacement
in Instrument Panel, Gauges and Console.
Is the replacement complete?
| --
|
Go to Step 5
| --
|
4
| Repair short to ground in circuit 1692 between cavity 1 of the Navigation
Data Processor connector C1 and cavity 16 of the Navigation Display Module
connector C2. Refer to
Wiring Repairs
in Wiring Systems.
Is the repair complete?
| --
|
Go to Step 5
| --
|
5
|
- Clear DTC with scan tool.
- Cycle the Ignition Switch.
- Perform Navigation Diagnostic System Check.
Has the test run and passed?
| --
| Go to
Diagnostic System Check - Navigation System
| --
|
