DCM Data Signal Circuit between Navigation ECU and DCM [10/2019 - ]: Procedure

1. Disconnect the I154 radio receiver assembly connector.
2. Disconnect the I189 DCM (telematics transceiver) connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I154-10 (USBV) - I189-15 (USBV)	Always	Below 1 Ω
   I154-11 (USBG) - I189-31 (USBG)	Always	Below 1 Ω
   I154-15 (VOT+) - I189-18 (VOR+)	Always	Below 1 Ω
   I154-16 (VOT-) - I189-34 (VOR-)	Always	Below 1 Ω
   I154-13 (VOR+) - I189-17 (VOT+)	Always	Below 1 Ω
   I154-14 (VOR-) - I189-33 (VOT-)	Always	Below 1 Ω
   I154-10 (USBV) - Body ground	Always	10 kΩ or higher
   I154-11 (USBG) - Body ground	Always	10 kΩ or higher
   I154-15 (VOT+) - Body ground	Always	10 kΩ or higher
   I154-16 (VOT-) - Body ground	Always	10 kΩ or higher
   I154-13 (VOR+) - Body ground	Always	10 kΩ or higher
   I154-14 (VOR-) - Body ground	Always	10 kΩ or higher
   I154-12 (SGND) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  2

1. Disconnect the I185 navigation ECU connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Navigation ECU)
   *b	Front view of wire harness connector (to DCM [Telematics Transceiver])

2. Disconnect the I191 DCM (telematics transceiver) connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I185-1 (USB+) - I191-2 (USB+)	Always	Below 1 Ω
   I185-2 (USB-) - I191-1 (USB-)	Always	Below 1 Ω
   I185-3 (USBS) - I191-3 (USBS)	Always	Below 1 Ω
   I185-1 (USB+) - Body ground	Always	10 kΩ or higher
   I185-2 (USB-) - Body ground	Always	10 kΩ or higher
   I185-3 (USBS) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [10/2019 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR