Toyota CH-R Service Manual: Communication Malfunction (Bus Ic) (B1497)

DESCRIPTION

The air conditioning harness assembly connects the air conditioning amplifier assembly and the servo motors. The air conditioning amplifier assembly supplies power and sends operation instructions to each servo motor through the air conditioning harness assembly. Each servo motor sends damper position information to the air conditioning amplifier assembly.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Memory

B1497

Communication Malfunction (Bus Ic)

Any of the following conditions is met:

  • Error in communication line
  • Open in communication line
  • Air conditioning harness assembly
  • No. 1 air conditioning radiator damper servo sub-assembly
  • Air conditioning amplifier assembly

Memorized

(10 seconds or more)*

  • *: The air conditioning amplifier assembly stores this DTC if the malfunction has occurred for the period of time indicated in the brackets.
DTC Detection Conditions
 

Vehicle Condition

Pattern 1

Pattern 2

Diagnosis Condition

Ignition switch ON

Malfunction Status

Error in communication line

-

Open in communication line

-

Detection Time

10 seconds or more

10 seconds or more

Number of Trips

1 trip

1 trip

HINT:

DTC will be output when conditions for either of the patterns in the table above are met.

WIRING DIAGRAM

PROCEDURE

1.

PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Air Conditioner / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

Body Electrical > Air Conditioner > Active Test

Tester Display

Measurement Item

Control Range

Diagnostic Note

Air Mix Servo Targ Pulse(D)

No. 1 air conditioning radiator damper servo sub-assembly (driver side air mix) pulse

Min.: 128

Max.: 383

Operates between 255 to 347 pulses

Body Electrical > Air Conditioner > Active Test

Tester Display

Air Mix Servo Targ Pulse(D)

OK:

No. 1 air conditioning radiator damper servo motor operates smoothly.

Result

Proceed to

No. 1 air conditioning radiator damper servo motors are malfunctioning

A

No. 1 air conditioning radiator damper servo motors is normal

B

B

GO TO STEP 4

A

2.

INSPECT AIR CONDITIONING HARNESS ASSEMBLY (AIR CONDITIONING AMPLIFIER ASSEMBLY - NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY)

NOTICE:

When inspecting the air conditioning amplifier assembly, do not bring the tester probes too close to each other as a short circuit may occur.

(a) Disconnect the m1 air conditioning amplifier assembly connector.

(b) Disconnect the No. 1 air conditioning radiator damper servo sub-assembly connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

m1-2 (BUS G) - Body ground

Always

Below 1 Ω

m1-3 (BUS) - 2 (LIN)

Always

Below 1 Ω

m1-4 (BUSB) - 1 (+B)

Always

Below 1 Ω

NG

REPLACE AIR CONDITIONING HARNESS ASSEMBLY

OK

3.

INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

NOTICE:

When inspecting the air conditioning amplifier assembly, do not bring the tester probes too close to each other as a short circuit may occur.

(a) Turn the ignition switch ON.

(b) Connect an oscilloscope to terminals m1-2 (BUS G) and m1-3 (BUS) of the air conditioning amplifier assembly and check the waveform.

OK:

Waveform is similar to that shown in the illustration.

HINT:

The waveform varies with the blower speed.

Item

Content

Tool Setting

2 V/DIV., 2 ms./DIV.

Vehicle Condition

Ignition switch ON.

*a

Component with harness connected

(Air Conditioning Amplifier Assembly)

OK

REPLACE NO. 1 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY

NG

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

4.

CHECK FOR DTC*

(a) Clear the DTCs.

Click here

Body Electrical > Air Conditioner > Clear DTCs

(b) Check for DTCs.

Click here

Body Electrical > Air Conditioner > Trouble Codes

Result

Proceed to

DTCs are not output

A

DTCs are output

B

A

USE SIMULATION METHOD TO CHECK

B

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    Refrigerant Shortage (B14B8)
    DESCRIPTION This DTC is stored if the amount of refrigerant in the air conditioning system is insufficient. The air conditioning amplifier assembly receives the ambient temperature signal, refri ...

    Compressor Solenoid Circuit (B1451)
    DESCRIPTION In this circuit, the cooler compressor assembly (compressor solenoid) receives a refrigerant compression demand signal from the air conditioning amplifier assembly. Based on this signa ...

    Other materials:

    Toyota CH-R Service Manual > Parking Brake: Parking Brake System
    Precaution PRECAUTION IGNITION SWITCH EXPRESSIONS (a) The type of ignition switch used on this model differs depending on the specifications of the vehicle. The expressions listed in the table below are used in this section. Expression Ignition Switch (Position) ...

    Toyota CH-R Service Manual > Occupant Classification System: Rear Occupant Classification Sensor LH Circuit Malfunction (B1782)
    DESCRIPTION The rear occupant classification sensor LH circuit consists of the occupant detection ECU and rear in weight detection sensor sub-assembly. DTC B1782 is stored when a malfunction is detected in the rear in weight detection sensor sub-assembly circuit. DTC No. ...

    © 2017-2019 Copyright www.tochr.net
    0.0157