DTC B1244: Light Sensor Circuit Malfunction [12/2012 - ]: Procedure

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [12/2012 - ] .

   Body Electrical > Main Body > Clear DTCs 

Result: 

NEXT 

See step  2

1. Check the DTCs.

   Refer to DTC CHECK / CLEAR [12/2012 - ] .

   Body Electrical > Main Body > Trouble Codes 

   Results	Proceed to
   	DTC B1244 output does not occur
   	DTC B1244 output occur

Result: 

DTC B1244 output does not occur 

USE SIMULATION METHOD TO CHECK: 

Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2012 - 11/2013] .

Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2013 - 10/2015] .

Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - 08/2016] .

Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - 08/2017] .

Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2017 - ] .

Result: 

DTC B1244 output occur 

See step  3

1. Using the Techstream, read the Data List.

   Refer to DATA LIST / ACTIVE TEST [12/2012 - ] .

   Body Electrical > Main Body > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Illumination Rate Info	Illumination rate information	0 ms. to 2162.65 ms.	Value output according to ambient light levels	-

   Body Electrical > Main Body > Data List 

   Tester Display
   Illumination Rate Info

   OK

   The display is as specified in the normal condition column.

Result: 

OK 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [12/2012 - ]  . 

Result: 

NG 

See step  4

1. Disconnect the G78 main body ECU (multiplex network body ECU) connector.
2. Disconnect the G2 automatic light control sensor connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G78-22 (CLTE) - G2-3 (CLTE)	Always	Below 1 Ω
   G78-21 (CLTS) - G2-5 (CLTS)	Always	Below 1 Ω
   G78-20 (CLTB) - G2-6 (CLTB)	Always	Below 1 Ω
   G78-22 (CLTE) - Body ground	Always	10 kΩ or higher
   G78-21 (CLTS) - Body ground	Always	10 kΩ or higher
   G78-20 (CLTB) - Body ground	Always	10 kΩ or higher

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

1. Remove the instrument panel junction block assembly and main body ECU (multiplex network body ECU) as a unit with the connectors still connected.

   Refer to REMOVAL [12/2012 - ] .

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component with harness connected (Main Body ECU [Multiplex Network Body ECU])

2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   G78-20 (CLTB) - G78-22 (CLTE)	Ignition switch off	Below 1 V
   	Ignition switch ON	11 to 14 V

Result: 

NG 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [12/2012 - ]  . 

Result: 

OK 

See step  6

1. Check the automatic light control sensor.

   Refer to REMOVAL [12/2012 - ] .

Result: 

OK 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [12/2012 - ]  . 

Result: 

NG 

REPLACE AUTOMATIC LIGHT CONTROL SENSOR. Refer to  REMOVAL [12/2012 - ]  .