DTC U0198: Lost Communication with Telematic Control Module [10/2015 - 11/2017]: Procedure

Body Electrical > Gateway > Trouble Codes 

1. Reconfirm DTCs.

   HINT: 

   If DTC U1002 is output from Gateway of the network gateway ECU, this indicates a sub bus 2 or sub bus 18 malfunction. Troubleshoot for DTC U1002 and check for malfunctions in sub bus 2 or sub bus 18.

   Result

   Result	Proceed to
   DTC U1002 is not output from network gateway ECU (Techstream display: Gateway)	A
   DTC U1002 is output from network gateway ECU (Techstream display: Gateway)	B

Result: 

B 

GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC. Refer to  DTC U1002: Lost Communication with Gateway Module (Network Gateway ECU) [10/2015 - 08/2016]  , or refer to  DTC U1002: Lost Communication with Gateway Module (Network Gateway ECU) [08/2016 - 11/2017] 

Result: 

A 

See step  2

1. Disconnect the cable from the negative (-) battery terminal.
2. Disconnect the O65 telematics transceiver connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Telematics Transceiver)

3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   O65-15 (CANP) - O65-16 (CANN)	Cable disconnected from negative (-) battery terminal	54 to 69 Ω

   Result

   Result
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (TELEMATICS TRANSCEIVER) 

Result: 

OK 

See step  3

1. Measure the resistance according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Telematics Transceiver)

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   O65-4 (E) - Body ground	Cable disconnected from negative (-) battery terminal	Below 1 Ω

2. Reconnect the cable to the negative (-) battery terminal.
3. Measure the voltage according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Telematics Transceiver)

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   O65-1 (+B) - Body ground	Always	11 to 14 V
   O65-7 (IG2) - Body ground	Engine switch on (IG)	11 to 14 V
   O65-8 (ACC) - Body ground	Engine switch on (ACC)	11 to 14 V

   Result

   Result
   OK
   NG

Result: 

OK 

REPLACE TELEMATICS TRANSCEIVER. Refer to  REMOVAL [09/2014 - 11/2017] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)