B1418

AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1418/18: Exhaust Gas Sensor Circuit

DTC B1418/18 - Exhaust Gas Sensor Circuit

DESCRIPTION

This sensor detects the exhaust gas outside the vehicle and sends appropriate signals to the A/C amplifier.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM (EMISSION GAS SENSOR)
(a) Check the Data List for proper functioning of the emission gas sensor.

Air Conditioner





OK:
The display is as specified in the normal condition.

Result:





C -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY
B -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
A -- Continue to next step.
2. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY (DGS - SG-1 VOLTAGE)




(a) Remove the A/C amplifier but do not disconnect the connector.
(b) Turn the ignition switch ON.
(c) Measure the voltage of the connector.
Standard voltage:





HINT: As the temperature increases, the voltage decreases.

Result:





C -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY
B -- PROCEED TO NEXT CIRCUIT INSPECTION
SHOWN IN PROBLEM SYMPTOMS TABLE
A -- Continue to next step.
3. INSPECT COOLER SENSOR (SMOG VENTILATION THERMISTOR)




(a) Remove the cooler sensor.
(b) Connect the positive (+) lead from the battery to the terminal 4 (IG) and the negative (-) lead to terminal 1 (GND).
(c) Apply battery positive voltage between terminals 1 and 4 for more than 30 seconds.
(d) Measure the resistance of the cooler.
Standard resistance:





HINT: When the cooler is exposed to the exhaust gas, the resistance goes down.

NG -- REPLACE COOLER SENSOR (SMOG VENTILATION THERMISTOR)
OK -- Continue to next step.
4. CHECK WIRE HARNESS (COOLER SENSOR - A/C AMPLIFIER AND BATTERY AND BODY GROUND)




(a) Disconnect the E10 cooler sensor connector.
(b) Disconnect the A9 amplifier connector.
(c) Measure the voltage of the wire harness side connectors.
Standard voltage:





(d) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY