Inspection Procedure

INSPECT COMMUNICATION FUNCTION OF LARGE-SCALE MULTIPLEX COMMUNICATION SYSTEM (BEAN)
1. Use the hand-held tester to check for normal function of the multiplex communication system.
  1. (ECU unconnected, communication line malfunctioning) Without DTC B1214, B1215 or B1262 outputs, proceed to A.
  2. (ECU unconnected, communication line malfunctioning) With DTC B1214, B1215 or B1262 outputs, proceed to B.
1. B: Go to MULTIPLEX COMMUNICATION SYSTEM (See DIAGNOSTIC TROUBLE CODE CHART )
2. A: Go to next step.
INSPECT FUSE (HEATER, RR-DEF)
1. Remove the HEATER fuse from the instrument panel J/B.
2. Remove the RR-DEF fuse from the FL block.
3. Check the resistance.
  Standard: Below 1 Ω
1. NG: REPLACE FUSE
2. OK: Go to next step.

CHECK VOLTAGE (J/B NO. 2)

Check the voltage of the terminal of the J/B.

Fig 1: Identifying IGI and RDB Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard:

STANDARD TESTER CONNECTION SPECIFICATION

Tester Connection.	Switch Position	Specified Condition
2B-8 (RDB) - Body ground	Constant	10 to 14 V
2B-9 (IG1) - Body ground	Ignition switch ON	10 to 14 V

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)
OK: Go to next step.

CHECK MODE MONITOR TERMINAL (J/B NO. 2)
1. Check the voltage of the terminal to the following condition.
  - Engine is running.
  - A/C switch is OFF.
  - Rear defogger and Deicer switch is ON
    Standard: 6.3 +/- 2 V
1. NG: Go to step 7
2. OK: Go to next step.
CHECK A/C AMPLIFIER ASSY (See HOW TO PROCEED WITH TROUBLESHOOTING )
1. NG: REPLACE A/C AMPLIFIER ASSY
2. OK: Go to next step.

CHECK WIRE HARNESS (A/C AMPLIFIER ASSY - J/B NO. 2 AND BODY GROUND)

Disconnect the A8 amplifier and 2H J/B connectors.

Fig 3: Disconnecting A8 Amplifier And 2H J/B Connectors

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check the resistance of the wire harness side connectors.

Standard:

TESTER CONNECTION SPECIFICATION

Tester Connection	Specified Condition
A8-19 (DFG) - 2H-11 (DEF)	Below 1 Ω
A8-6 (GND) - Body ground	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: Go to next step.

CHECK J/B NO. 2 (RR-DEF RELAY)

Remove the J/B.
Connect the battery positive (+) lead to terminal 2B-8 (RDB) and battery negative (-) terminal lead to terminal 2H-13 (SGND), 2F-1 (PGND) and 2H-11 (DEF).

Check the voltage of the RR-DEF relay terminals.

Fig 4: Checking J/B No. 2 (RR-DEF Relay)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard:

TESTER CONNECTION SPECIFICATION

Tester Connection	Specified Condition
2B-7 (RDL) - 2H-13 (SGND)	OV

Connect another battery positive (+) lead to terminal 2B-9 (IG1).

Check the voltage of the RR-DEF relay terminals.

Standard:

TESTER CONNECTION SPECIFICATION

Tester Connection	Specified Condition
2B-7 (RDL) - 2H-13 (SGND)	10 to 14 V

NG: REPLACE J/B NO. 2
OK: Go to next step.

CHECK WIRE HARNESS (REAR WINDOW DEFOGGER - J/B NO. 2 AND BODY GROUND)

Disconnect the N4, N5 defogger and 2B J/B connectors.

Fig 5: Disconnecting N4, N5 Defogger And 2B J/B Connectors

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check the resistance of the wire harness side connectors.

Standard:

TESTER CONNECTION SPECIFICATION

Tester Connection	Specified Condition
N4-1 - 2B-7 (RDL)	Below 1 Ω
N5-1 - Body ground	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: Go to next step.

CHECK REAR WINDOW DEFOGGER WIRE

NOTE:

When cleaning the glass, wipe the glass along the wire using a soft and dry cloth. Take care not to damage the wires.
Do not use detergents or glass cleaners including abrasive ingredients.
When measuring voltage, wrap a piece of tin foil around the tip of the negative probe and press the foil against the wire with your finger, as shown in the illustration

Fig 6: Wrapping Piece Of Tin Foil Around Tip Of Negative Probe And Pressing Foil Against Wire With Your Finger
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Turn the ignition switch ON.
Turn the defogger switch ON.

Check the voltage at the center of each defogger wire, as shown in the illustration.

Standard:

VOLTAGE SPECIFICATION

Voltage	Criteria
Approx. 5 V	Okay, wire is not broken
Approx. 10 V or O V	Wire is broken

Fig 7: Checking Voltage At Center Of Each Defogger Wire

HINT:

If there is approx 10 V, the wire may be broken between the center of the wire and the end on the battery side. If there is no voltage, the wire may be broken between the center of the wire and the end on the ground side.

Place the voltmeter positive (+) lead against the defogger wire on the battery side.
Place the voltmeter negative (-) lead with the foil strip against the wire on the ground side.
Slide the positive (+) lead from the battery side to the ground side.

Fig 8: Placing Voltmeter (+) Lead Against Defogger Wire On Battery Side And Placing Voltmeter Negative (-) Lead With Foil Strip Against Wire On Ground Side
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
The point where the voltmeter deflects from approx. 10 V V to 0 V is the place where the defogger wire is broken.
HINT:

If the defogger wire is not broken, the voltmeter indicates 0 V at the positive (+) end of the defogger wire but gradually increases to approx 12 V as the meter probe moves to the other end.

NG: REPAIR REAR WINDOW DEFOGGER WIRE (See INSPECTION )
OK: SYSTEM NORMAL