DESCRIPTION
This circuit detects the engine switch on (ACC) or off condition, and sends it to the main body ECU (multiplex network body ECU).
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
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PROCEDURE
1. | CHECK FOR DTC (SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function)) |
(a) Clear the DTCs.
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(b) Check for the DTCs.
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Result | Proceed to |
---|---|
Smart Access System with Push-button Start (for Start Function) DTCs are not output | A |
Smart Access System with Push-button Start (for Start Function) DTCs are output | B |
B | ![]() | GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) |
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2. | READ VALUE USING TECHSTREAM |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Main Body / Data List.
(e) Read the Data List according to the display on the Techstream.
Body Electrical > Main Body > Data List Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
---|---|---|---|---|
ACC SW | Engine switch on (ACC) signal | ON or OFF | ON: Engine switch on (ACC) OFF: Engine switch off | - |
Tester Display |
---|
ACC SW |
OK:
Normal conditions listed above are displayed.
OK | ![]() | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
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3. | CHECK HARNESS AND CONNECTOR (POWER SOURCE - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) |
(a) Disconnect the 2E instrument panel junction block assembly connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
---|---|---|
2E-1 - Body ground | Always | 11 to 14 V |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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4. | INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
(a) Remove the instrument panel junction block assembly.
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(b) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
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(c) Measure the resistance according to the value(s) in the table below.
*a | Component without harness connected (Instrument Panel Junction Block Assembly) | - | - |
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
2E-1 - MB-30 (ACC) | Battery not connected to 2A-30 and 2B-3 | 10 kΩ or higher |
2E-1 - MB-30 (ACC) | Battery positive (+) → 2A-30 Battery negative (-) → 2B-3 | Below 1 Ω |
OK | ![]() | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
NG | ![]() | REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
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