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Without Lexus Hand-Held Tester

Codes from multiplex self-diagnostic system are retrieved through Data Link Connector 1 (DLC1), located in engine compartment, near ECM. With key on, engine off, connect jumper wire between DLC1 terminal E1 and terminal Tc. See Fig 1. Trouble codes are displayed as flashes of open door indicator light, located in instrument panel. All trouble codes are 2-digit numbers. Pay careful attention to length of pauses in order to read codes correctly. If any code is present, perform test(s) in order given. See MULTIPLEX TROUBLE CODE DEFINITION  table.

Fig 1: Identifying Data Link Connector 1 (DLC1) Terminals
G93G02766Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
MULTIPLEX TROUBLE CODE DEFINITION (1)

Code No. Description Perform Test:
11 Body No. 1 ECU To Driver Door ECU Communication 1 
12 Body No. 1 ECU To Passenger Door ECU Communication 2 
13 Body No. 1 ECU To Tilt/Telescopic ECU Communication 3 
14 Door System Communication Bus Short To Battery Voltage 4 
15 Door System Communication Bus Shorted To Ground 4 
16 Body No. 1 ECU To Right Rear Door ECU Communication 5 
17 Body No. 1 ECU To Left Rear Door ECU Communication 6 
18 Body No. 2 ECU Communication 7 
21 Power Window Master Switch Circuit 8 
22 Driver Key Lock & Unlock Switch Circuit 8 
23 Passenger Power Window Switch Circuit 8 
24 Passenger Key Lock & Unlock Switch Circuit 8 
25 Right Rear Door Power Window Switch Circuit 8 
26 Left Rear Door Power Window Switch Circuit 8 
31 Driver Door Jam Limit Switch Circuit 9 
32 Driver Door Pulse Limit Switch Circuit 10 
33 Passenger Door Jam Limit Switch Circuit 9 
34 Passenger Door Pulse Limit Switch Circuit 10 
35 Right Rear Door Jam Limit Switch Circuit 9 
36 Right Rear Door Pulse Limit Switch Circuit 10 
37 Left Rear Door Jam Limit Switch Circuit 9 
38 Left Rear Door Pulse Limit Switch Circuit 10 
41 Body No. 1 ECU Switch Circuit (Trunk) 8 
42 Remote Keyless Entry Circuit 11 
43 GSW Terminal Circuit 12 
44 Light Sensor Circuit 13 
52 Body No. 2 ECU Switch Circuit (Stoplight) 8 
53 Body No. 2 ECU GSW Terminal (Low) 12 
54 Body No. 2 ECU GSW Terminal (High) 12 
55 Body No. 2 ECU P1 Switch 14 
61 Body No. 1 ECU To ECM Communication 15 
62 Body No. 1 ECU To A/C ECU Communication 16 
66 Instrument Communication Bus Short To Battery Voltage 17 
67 Instruments Communication Bus Shorted To Ground 17 
71 Instrument Panel ECU Communication 18 
72 Power Seat ECU Communication 19 
73 Sun Roof ECU Communication 20 
75 Accessory Bus Buffer Communication (2)
(1) Codes are listed as 2-digit (without Lexus Hand-Held Tester). For tester codes, codes are preceded by B12.
(2) Check wiring harness of affected accessory.
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