AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System), Diagnostic DTC:B1417/17

DESCRIPTION

The No. 2 cooler thermistor (room temperature sensor) is installed on the evaporator in the rear air conditioning unit to detect the cooled air temperature that has passed through the evaporator and control the air conditioning. It sends appropriate signals to the air conditioning amplifier assembly. The resistance of the No. 2 cooler thermistor (room temperature sensor) changes in accordance with the cooled air temperature that has passed through the rear evaporator. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The air conditioning amplifier assembly applies voltage (5 V) to the No. 2 cooler thermistor (room temperature sensor) and reads voltage changes as the resistance of the No. 2 cooler thermistor (room temperature sensor) changes. This sensor is used for frost prevention.

WIRING DIAGRAM

PROCEDURE

1. READ VALUE USING GTS (AMBIENT TEMP SENS [REAR])

   
   

   1. Use the Data List to check if the No. 2 cooler thermistor (room temperature sensor) is functioning properly Click here.

      Air Conditioner

      Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
      Ambient Temp Sens (Rear)	No. 2 cooler thermistor / Min.: -29.7°C (-21.46°F), Max.: 59.55°C (139.19°F)	Actual rear evaporator temperature displayed	No. 2 air conditioning harness assembly (evaporator temperature sensor) system malfunction: Open in the circuit: -29.7°C (- 21.46°F) Short in the circuit: 59.55°C (139.19°F)

      OK
      The display is as specified in the normal condition.

      Result

      Result	Proceed to
      OK (When troubleshooting according to the DTC)	A
      OK (When troubleshooting according to Problem Symptoms Table)	B
      NG	C

   
   

   A

   REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

   B

   PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here

   C

2. INSPECT NO. 2 AIR CONDITIONING HARNESS ASSEMBLY (EVAPORATOR TEMPERATURE SENSOR)

   
   

   1. Remove the No. 2 air conditioning harness assembly (evaporator temperature sensor) Click here.

   2. Inspect the No. 2 air conditioning harness assembly (evaporator temperature sensor) Click here.

   
   

   NG

   REPLACE NO. 2 AIR CONDITIONING HARNESS ASSEMBLY Click here

   OK

3. CHECK HARNESS AND CONNECTOR (NO. 2 AIR CONDITIONING HARNESS ASSEMBLY -AIR CONDITIONING AMPLIFIER ASSEMBLY)

   
   

   1. Disconnect the K19 No. 2 air conditioning harness assembly connector.

   2. Disconnect the E35 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition K19-8 (+) - E35-11 (TEC) Always Below 1 Ω K19-7 (-) - E35-33 (SG) Always Below 1 Ω K19-7 (-) - K19-8 (+) Always 10 kΩ or higher K19-8 (+) or E35-11 (TEC)- Body ground Always 10 kΩ or higher K19-7 (-) or E35-33 (SG) - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

4. CHECK NO. 2 AIR CONDITIONING HARNESS ASSEMBLY

   
   

   1. Replace the No. 2 air conditioning harness assembly with a new or known good one Click here.

   2. When troubleshooting according to the DTC:

      
      

      1. Clear the DTCs Click here.

      2. Check for DTCs Click here.

         OK
         DC B1417/17 is not output.

   3. When troubleshooting according to Problem Symptoms Table:

      
      

      1. Check the air conditioning control system operates normally.

         OK
         Air conditioning control system operation returns to normal.

   
   

   OK

   END (NO. 2 AIR CONDITIONING HARNESS ASSEMBLY WAS DEFECTIVE)

   NG

   REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here