Smart Access System With Push-Button Start (For Entry Function)

2012 Lexus CT 200h L4-1.8L (2ZR-FXE) HybridSECTION Smart Access System With Push-Button Start (For Entry Function)




THEFT DETERRENT / KEYLESS ENTRY: SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Entry Function): TERMINALS OF ECU

1. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)





(a) Disconnect the H1 certification ECU (smart key ECU assembly) connector.

(b) Measure the voltage and resistance according to the value(s) in the table below.





* *: In order to prevent the auxiliary battery from being depleted when the vehicle is shipped long distances, a fuse that cuts unnecessary electrical load while the vehicle is being shipped is set in the circuit. If the fuse is removed, the circuit becomes open. If the fuse that is between the auxiliary battery and terminal CUTB is removed and the circuit is open, the certification ECU (smart key ECU assembly) changes to a certain control mode (example: the transmission of electric waves every 250 ms. that form the detection area stops).

If the result is not as specified, there may be a malfunction on the wire harness side or the fuse is removed.

(c) Reconnect the H1 certification ECU (smart key ECU assembly) connector.

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





















* *1: For details about the areas that are inside the entry function detection area, refer to Operation Check Operation Check.

* *2: For details about the areas that are outside the entry function detection area, refer to Operation Check Operation Check.

* *3: For details about the areas that are inside the wireless function operational area, refer to Operation Check Operation Check.

(e) Using an oscilloscope, check waveform 1.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Waveform 1 (Reference)





* *: For details about the areas that are inside the entry function detection area, refer to Operation Check Operation Check.

(f) Using an oscilloscope, check waveform 2.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Waveform 2 (Reference)





* *: For details about the areas that are outside the entry function detection area, refer to Operation Check Operation Check.

Waveform 2 (Reference)





* *: For details about the areas that are outside the entry function detection area, refer to Operation Check Operation Check.

(g) Using an oscilloscope, check waveform 3.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Text in Illustration





Waveform 3 (Reference)





(h) Using an oscilloscope, check waveform 4.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Text in Illustration





Waveform 4 (Reference)





(i) Using an oscilloscope, check waveform 5.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Text in Illustration





Waveform 5 (Reference)





Waveform 5 (Reference)





Waveform 5 (Reference)





Waveform 5 (Reference)





Waveform 5 (Reference)





Waveform 5 (Reference)





(j) Using an oscilloscope, check waveform 6.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Text in Illustration





Waveform 6 (Reference)





* *1: For details about the areas that are outside the entry function detection area, refer to Operation Check Operation Check.

* *2: For details about the areas that are inside the wireless function operational area, refer to Operation Check Operation Check.

(k) Using an oscilloscope, check waveform 7.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Text in Illustration





Waveform 7 (Reference)





* *1: For details about the areas that are outside the entry function detection area, refer to Operation Check Operation Check.

* *2: For details about the areas that are inside the wireless function operational area, refer to Operation Check Operation Check.

(l) Using an oscilloscope, check waveform 8.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Text in Illustration





Waveform 8 (Reference)





* *1: For details about the areas that are outside the entry function detection area, refer to Operation Check Operation Check.

* *2: For details about the areas that are inside the wireless function operational area, refer to Operation Check Operation Check.

2. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY AND MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)





(a) Remove the main body ECU from the instrument panel junction block assembly.

(b) Measure the voltage and resistance according to the value(s) in the table below.





If the result is not as specified, there may be a malfunction in the wire harness.

(c) Install the main body ECU to the instrument panel junction block assembly.

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













If the result is not as specified, the main body ECU (multiplex network body ECU) or instrument panel junction block assembly may have a malfunction.

(e) Using an oscilloscope, check waveform 1.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Waveform 1 (Reference)





Waveform 1 (Reference)





Waveform 1 (Reference)





Waveform 1 (Reference)





Waveform 1 (Reference)





Waveform 1 (Reference)





Waveform 1 (Reference)





(f) Using an oscilloscope, check waveform 2.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Waveform 2 (Reference)





Waveform 2 (Reference)





Waveform 2 (Reference)





Waveform 2 (Reference)





Waveform 2 (Reference)





Waveform 2 (Reference)





(g) Using an oscilloscope, check waveform 3.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Waveform 3 (Reference)





Waveform 3 (Reference)





(h) Using an oscilloscope, check waveform 4.

HINT
The oscilloscope waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.





Waveform 4 (Reference)





Waveform 4 (Reference)





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