Lexus NX: Terminals Of Ecu
TERMINALS OF ECU
CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY, MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)
| *1 | Main Body ECU (Multiplex Network Body ECU) | - | - |
(a) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
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(b) Connect the instrument panel junction block assembly connectors.
(c) Measure the voltage and resistance according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A-32 (IG) - Body ground | - | Ignition power supply | Power switch on (IG) | 11 to 14 V |
| Power switch off | Below 1 V | |||
| A-31 (BECU) - Body ground | - | Battery power supply | Power switch off | 11 to 14 V |
| A-30 (ACC) - Body ground | - | ACC power supply | Power switch on (ACC) | 11 to 14 V |
| Power switch off | Below 1 V | |||
| A-11 (GND1) - Body ground | - | Ground | Always | Below 1 Ω |
If the result is not as specified, there may be a malfunction in the wire harness or instrument panel junction block assembly.
(d) Install the main body ECU (multiplex network body ECU).
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(e) Measure the voltage and pulse according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| I48-6 (FLCY) - Body ground | G - Body ground | Front door courtesy light switch LH signal | Front door LH open | Below 1 V |
| Front door LH closed | Pulse generation | |||
| I48-27 (FRCY) - Body ground | W - Body ground | Front door courtesy light switch RH signal | Front door RH open | Below 1 V |
| Front door RH closed | Pulse generation | |||
| I47-2 (LSWR) - Body ground | Y - Body ground | Rear door unlock detection switch RH signal | Rear door RH unlocked | Below 1 V |
| Power switch off, all doors closed and rear door RH locked | Pulse generation | |||
| 4D-39 (LSFR) - Body ground | P - Body ground | Front door unlock detection switch RH signal | Front door RH unlocked | Below 1 V |
| Power switch off, all doors closed and front door RH locked | Pulse generation | |||
| 4D-37 (RCTY) - Body ground | Y - Body ground | Rear door courtesy light switch RH signal | Rear door RH open | Below 1 V |
| Rear door RH closed | Pulse generation | |||
| 4A-34 (LSWL) - Body ground | Y - Body ground | Rear door unlock detection switch LH signal | Rear door LH unlocked | Below 1 V |
| Power switch off, all doors closed and rear door LH locked | Pulse generation | |||
| 4A-21 (BCTY) - Body ground | R - Body ground (w/o Rear Power Seat System) LG - Body ground (w/ Rear Power Seat System) | Back door courtesy light switch signal | Back door open | Below 1 V |
| Back door closed | 11 to 14 V | |||
| 4A-18 (LCTY) - Body ground | W - Body ground | Rear door courtesy light switch LH signal | Rear door LH open | Below 1 V |
| Rear door LH closed | Pulse generation | |||
| 4D-40 (LSFL) - Body ground | B - Body ground | Front door unlock detection switch LH signal | Front door LH unlocked | Below 1 V |
| Power switch off, all doors closed and front door LH locked | Pulse generation | |||
| 4C-46 (DOMR) - Body ground | R - Body ground | Battery saving control (interior light auto cut function) signal | Battery saving control (interior light auto cut function) operating | Below 1 V |
| Battery saving control (interior light auto cut function) not operating | 11 to 14 V | |||
| 4C-39 - Body ground | B - Body ground | Headlight dimmer switch tail signal | Headlight dimmer switch in tail position | Below 1 V |
| Headlight dimmer switch not in tail position | 11 to 14 V | |||
| 4D-36 (ILE) - Body ground | SB - Body ground | Map light and spot light signal | Map light and spot light on using illuminated entry system | Below 1 V |
| Map light and spot light off using illuminated entry system | 11 to 14 V | |||
| 4D-32 (FSPT) - Body ground | W - Body ground | Interior illumination light LH signal | Interior illumination LH light on | Below 1 V |
| Interior illumination LH light off | 11 to 14 V | |||
| 4D-33 (FSPT) - Body ground | B - Body ground | Interior illumination light RH signal | Interior illumination RH light on | Below 1 V |
| Interior illumination RH light off | 11 to 14 V | |||
| I47-4 (MILE) - Body ground | P - Body ground | Door outside handle illumination light signal | Door outside handle illumination light on | 11 to 14 V |
| Door outside handle illumination light off | Below 1 V | |||
| I47-27 (DMDR) - Body ground | W - Body ground | Map light door switch signal input | Map light door switch on | Below 1 V |
| Map light door switch off | 11 to 14 V | |||
| I47-28 (DMON) - Body ground | B - Body ground | Map light front dome light switch signal input | Map light front dome light switch on | Below 1 V |
| Map light front dome light switch off | Pulse generation |
CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
(a) Disconnect the I53 certification ECU connector.
(b) Measure the voltage and resistance according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| I53-10 (+B) - Body ground | W - Body ground | Battery power supply | Power switch off | 11 to 14 V |
| I53-11 (E) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
If the result is not as specified, there may be a malfunction on the wire harness side.
(c) Reconnect the I53 certification ECU connector.
(d) Measure the voltage according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| I53-17 (SWIL) - I53-12 (AGND) | BE - P | Power switch illumination operation signal | Power switch illumination on | 11 to 14 V |
| Power switch illumination off | Below 1 V |
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