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For 1990-2009 cars only

DTC B2461 Navigation ECU Synchronous Signal Error 98

Circuit Description

When the Navigation Display Module is running through System Inspection Mode, it tests the periodic synchronous signal.

Conditions for Running the DTC

Navigation Display Module is running through System Inspection Mode.

Conditions for Setting the DTC

No periodic synchronous signal is detected by the Navigation Display Module.

Action Taken When the DTC Sets

    • NAV sync. abnormality appears on the display.
    • 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:
       - Mis-routed harness
       - 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 B2461 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.

  1. Determines if the malfunction is present.

  2. Checks for poor connections at the Navigation Data Processor and at the Navigation Display Module.

  3. Determines if the malfunction is due to an internal fault in the Navigation Data Processor.

  4. Determines if the malfunction is due to an internal fault in the Navigation Display Module.

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

Inspect for poor connections at the Navigation Data Processor and the Navigation Display Module.

Was a poor connection found?

--

Go to Step 3

Go to Step 4

3

  1. Repair poor connection.
  2. Clear DTC with the scan tool.
  3. Cycle the Ignition Switch.
  4. Perform Navigation Diagnostic System Check.

Has the test run and passed?

--

Go to Diagnostic System Check - Navigation System

--

4

Exchange the Navigation Data Processor with a known good unit. Refer to Navigation Data Processor Replacement in Body Rear End.

Is the exchange complete?

--

Go to Step 5

--

5

  1. Clear DTC with the scan tool.
  2. Cycle the Ignition Switch.
  3. Perform Navigation Diagnostic System Check.

Has the test run and passed?

--

Go to Diagnostic System Check - Navigation System

Go to Step 6

6

Exchange the Navigation Display Module with a known good unit. Refer to Navigation Display Module Replacement in Instrument Panel, Gages, and Console.

Is the exchange complete?

--

Go to Step 7

--

7

  1. Clear DTC with the scan tool.
  2. Cycle the Ignition Switch.
  3. Perform Navigation Diagnostic System Check.

Has the test run and passed?

--

Go to Diagnostic System Check - Navigation System

--