COMPONENT PARTS
Component Parts Location
SYSTEM
CAN COMMUNICATION SYSTEM
CAN COMMUNICATION SYSTEM : System Description
SYSTEM DIAGRAM
DESCRIPTION
CAN Communication Signal Generation
NOTE: A signal with no current passage is called “Recessive” and one with current passage is called “Dominant”.
The Construction of CAN Communication Signal (Message)
No. |
Message name |
Description |
1 | Start of frame (1 bit) | Start of message. |
2 | Arbitration of field (11 bit) | Priorities of message-sending are shown when there is a possibility that multiple messages are sent at the same time. |
3 | Control field (6 bit) | Signal quantity in data field is shown. |
4 | Data field (0-64 bit) | Actual signal is shown. |
5 | CRC field (16 bit) |
|
6 | ACK field (2 bit) | The completion of normal reception is sent to the transmitting unit. |
7 | End of frame (7 bit) | End of message. |
CAN Communication Line
The CAN communication line is a twisted pair wire consisting of strands of CAN-H 1 and CAN-L 2 and has noise immunity.
NOTE: The CAN communication system has the characteristics of noise-resistant because this system produces digital signals by using the potential difference between the CAN-H line and the CAN-L line and has the twisted pair wire structure.
Since the CAN-H line and the CAN-L line are always adjacent to each other, the same degree of noise occurs, respectively, when a noise 1 occurs. Although the noise changes the voltage, the potential difference 2 between the CAN-H line and the CAN-L line is insensitive to noise. Therefore, noise-resistant signals can be obtained.
CAN Signal Communications
Each control unit of the CAN communication system transmits signals through the CAN communication control circuit included in the control unit and receives only necessary signals from each control unit to perform various kinds of control.
NOTE: The above signal names and signal communications are provided for reference purposes. For CAN communications signals of this vehicle, refer to LAN-32, "CAN COMMUNICATION SYSTEM : CAN Communication Signal Chart".
CAN COMMUNICATION SYSTEM : CAN Communication Control Circuit
CAN communication control circuit is incorporated into the control unit and transmits/receives CAN communication signals.
Component |
System description |
CAN controller | It controls CAN communication signal transmission and reception, error detection, etc. |
Transceiver IC | It converts digital signal into CAN communication signal, and CAN communication signal into digital signal. |
Noise filter | It eliminates noise of CAN communication signal. |
Termination circuit* (Resistance of approx. 120 Ω) | Generates a potential difference between CAN-H and CAN-L. |
*: These are the only control units wired with both ends of CAN communication system.
CAN COMMUNICATION SYSTEM : CAN System Specification Chart
Determine CAN system type from the following specification chart.
NOTE: Refer to LAN-17, "Trouble Diagnosis Procedure" for how to use CAN system specification chart.
×: Applicable
*1: With auto A/C
*2: Without auto A/C
VEHICLE EQUIPMENT IDENTIFICATION INFORMATION
NOTE: Check CAN system type from the vehicle shape and equipment.
CAN COMMUNICATION SYSTEM : CAN Communication Signal Chart
Refer to LAN-16, "How to Use CAN Communication Signal Chart" for how to use CAN communication signal chart.
NOTE: Refer to LAN-22, "Abbreviation List" for the abbreviations of the connecting units.
NOTE: CAN data of the air bag diagnosis sensor unit is not used by usual service work, thus it is omitted.
P0037, P0038 HO2S2 heater
DTC Description
DTC DETECTION LOGIC
DTC No.
CONSULT screen terms
(Trouble diagnosis content)
DTC detecting condition
P0037
HO2S2 HTR (B1)
(HO2S heater control circuit low bank 1
sensor 2)
The current amperage in the heated oxygen sensor 2 heater circuit is
...
Idle air volume learning
Description
Idle Air Volume Learning is a function of ECM to learn the idle air volume
that keeps each engine idle speed
within the specific range. It must be performed under any of the following
conditions:
Each time electric throttle control actuator or ECM is replaced.
Idle spee ...
Instrument cluster
Principle
The instrument cluster is a variable display.
When you change to a different program via Driving
Dynamics Control, the displays in the instrument
cluster adapt to the respective driving
mode.
General information
Depending on the vehicle equipment, it may be
possible to deactivate the disp ...