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Home >> Lexus >> 2003 >> GS 430 >> Repair and Diagnosis >> External Pages >> Different car >> Section 198 (LEXUS Navigation System) >> Circuit Inspection >> 12. Map DISC cannot be inserted. >> Inspection Procedure
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Inspection Procedure

WARNING: This page is about a different car, the 2004 Lexus GS 430 and 2004 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check the MAP DISC. 
    1. NG: Replace the MAP DISC. 
    2. OK: Go to Next Step 
  2. Insert a MAP DISC without tilt. 
    1. OK: Normal. 
    2. NG: Go to Next step 
  3. Check the navigation ECU. 

    PREPARATION: 

    Disconnect the navigation ECU connector.

    CHECK: 

    Check voltage terminals +B.

    OK: 

    +B: 10 - 14 V 

    CHECK: 

    Check voltage terminal ACC when turn ignition switch ACC or ON position.

    OK: 

    ACC: 10 - 14 V 

    CHECK: 

    Check continuity terminal GND.

    OK: 

    GND: Continuity 

    1. NG: Replace or repair wire harness. 
    2. OK: Go to next step. 

    Replace the navigation ECU.