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For 1990-2009 cars only

Diagnostic System Check - Navigation System 98

Circuit Description

The Navigation Diagnostic System Check is an organized approach to identify problems associated with the module. This check must be the starting point for any module complaint, and will direct you to the next logical step in diagnosing the complaint. The module is a very reliable component and is not likely the cause of the malfunction. Most system complaints are linked to faulty wiring and connectors, and occasionally to components. Understanding the computer system and using the tables correctly will reduce diagnostic time and prevent unnecessary parts replacement.

Diagnostic Aids

    • The following conditions may result in an intermittent operation of the module with no DTC stored:
       - Any condition which results in the interruption of power to the module
       - Out of range battery or ignition voltage

Specification
Normal module operating voltage: 9.0-16.0 V

       - A loose or damaged ground(s)
       - An open or shorted serial data line
    • An intermittent failure in the electronic system may be very difficult to detect and to accurately diagnose. The module tests for different malfunctions under different vehicle conditions. For this reason, a thorough test drive is often needed in order to repeat a malfunction. If the system malfunction is not repeated during the test drive, a good description of the complaint may be very useful in locating an intermittent malfunction. Faulty electrical connections or wiring causes most intermitting problems. When an intermitting condition is suspected, check the suspected circuits for the following conditions:
       - Poor mating of connector halves or backed out terminals
       - Improperly formed or damaged terminals
       - Wire chafing
       - Poor wire-to-terminal connections
       - Dirty or corroded terminals
       - Damage to connector bodies
    • Use the J 35616 whenever a diagnostic procedure requests probing or checking a terminal. Using this adapter will ensure that no damage to the terminal will occur, and will give an idea of whether contact tension is sufficient.
    • If the DTC is a history DTC, the problem may be intermittent. Perform the tests shown while moving related wiring and connectors. This can often cause the malfunction to occur. Perform a thorough inspection of all related wiring and connectors pertaining to the history DTC stored. Refer to Intermittents and Poor Connections Diagnosis
    • Exit all scan tool tests before cycling the ignition OFF to ON unless the scan tool instructions direct otherwise. Follow the operating instructions in the scan tool operator's manual. Failure to follow these instruction may set DTCs, cause vehicle system malfunctions, set false DTCs, or cause scan tool malfunctions.

Test Description

The numbers below refer to the step numbers on the diagnostic table:

  1. This test determines if communication can be established with the module.

  2. This test checks for stored module DTCs.

  3. This test checks for stored module Loss of Class 2 Serial Data Communication DTCs.

  4. This test determines whether communication can be established with other modules connected to the Class  2 serial data line.

  5. This test checks for any open module power fuses.

  6. This test checks the module power circuit. If the test light does not turn on, there is an open in the module power circuit.

  7. This test checks the module ground circuit. If the test light does not turn on, there is an open in the module power circuit.

Step

Action

Value(s)

Yes

No

1

  1. Turn off the ignition switch.
  2. Install a scan tool.
  3. Turn on the ignition switch.
  4. Attempt to establish communication with the Navigation Data Processor.

Does the scan tool communicate with the module?

--

Go to Step 2

Go to Step 4

2

Select display Navigation DTC function with the scan tool.

Are any DTCs stored?

--

Go to Step 3

System OK

3

Are any Loss of Class 2 Serial Data Communication DTCs set? (Loss of Class 2 Serial Data Communication DTCs have the form UXXXX.)

--

Go to Diagnostic Trouble Code (DTC) List/Type in Body Control System

Go to Navigation System DTC List

4

Attempt to establish communications with the other modules connected to the same serial data line (PCM, RFA, IPC, etc.).

Does the scan tool communicate with the other modules?

--

Go to Step 5

Go to Scan Tool Does Not Communicate with Class 2 Data Line in Wiring Systems

5

  1. Turn on the ignition switch.
  2. With a test light connected to ground, probe each Navigation fuse.

Does the test light turn on in all circuits?

--

Go to Step 6

Go to Step 8

6

  1. Turn off the ignition switch.
  2. Disconnect the Navigation Data Processor connectors.
  3. Turn on the ignition switch.
  4. With a test light connected to ground, probe all module power circuits.

Does the test light turn on in all circuits?

--

Go to Step 7

Go to Step 10

7

With a test light connected to Battery Positive Voltage (B+), probe all Navigation Data Processor ground circuits.

Does the test light turn on in all circuits?

--

Go to Step 9

Go to Step 11

8

  1. Repair the open in the ignition or battery feed to Navigation fuse.
  2. If the fuse is open, locate and repair the short to ground in the circuit connected to the open fuse.

Is the repair complete?

--

Go to Step 12

--

9

Replace the Navigation Data Processor. Refer to Navigation Data Processor Replacement

Is the repair complete?

--

Go to Step 12

--

10

Locate and repair the open in the Navigation power circuit.

Is the repair complete?

--

Go to Step 12

--

11

Locate and repair the open in the Navigation ground circuit.

Is the repair complete?

--

Go to Step 12

--

12

  1. Turn off the ignition switch.
  2. Connect or install any connectors or components that were disconnected or removed.
  3. Clear all DTCs. Refer to Clearing DTCs.

Are all DTCs cleared?

--

System OK

--