Inspection Procedure

WARNING: This page is about a different car, the 2003 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.

Inspect Navigation ECU (+B, ACC, GND)
1. Remove the navigation ECU with connectors with still connected.
  
  Fig 1: Inspecting Navigation ECU Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check voltage.
  1. Measure voltage between terminals +B, ACC and GND of navigation ECU at each conditions, as shown in Fig 2.
  Standard:
  
  Fig 2: Terminal Voltage Specifications
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Check continuity.
  1. Check that the continuity exists between terminal GND of navigation ECU and body ground.
  Standard: Continuity exists.
1. NG: Repair Or Replace Harness Or Connector
2. OK: Go To Next Step

Inspect Navigation ECU (SYNC, VR, VG)

Check continuity.
1. Check that the continuity exists between each terminal, as shown in Fig 4.
  
  Fig 3: Inspecting Navigation ECU Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard:

Fig 4: Terminal Continuity Specifications
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check signal waveform.

Fig 5: Navigation ECU Signal Waveform

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Using an oscilloscope, check signal waveform between terminals SYNC and GND of navigation ECU

NAVIGATION ECU VOLTAGE SYSTEM

Item	Contents
Tool Setting	500mV/DIV, 10 us/DIV
Condition	Navigation Display Is Displayed

NOTE: Signal wave form is shown in Fig 5.

NG: Check And Replace Radio Receiver Assembly
OK: Go To Next Step

Inspect Radio Receiver Assembly (SYNC, VR, VG)

Check continuity.
1. Check that the continuity exists between each terminals, as shown in Fig 7.
  
  Fig 6: Inspecting Radio Receiver Assembly Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard:

Fig 7: Radio Receiver Terminal Continuity Table
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check signal waveform.

Fig 8: Radio Receiver Signal Waveform

Using an oscilloscope, check signal waveform between terminals SYNC and GND of radio receiver assembly.

RADIO RECEIVER ITEMS - CONTENT

Item	Contents
Tool Setting	500mV/DIV, 10 us/DIV
Condition	Navigation Display Is Displayed

NOTE: Signal wave form is shown in Fig 8.

NG: Repair Or Replace Harness Or Connector
OK: Check And Replace Radio Receiver Assembly