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B1209

DTC B1209 INTAKE POTENTIOMETER SHORT

Component Location:




COMPONENT LOCATION

GENERAL DESCRIPTION
Intake door located at heater unit controls the inlet of car. When driver operates the intake switch, A/C controller recirculationeives mode signal from intake switch and operates intake door actuator to turn intake door to intended position. (with fresh mode signal, intake door is closed and with fresh mode signal, intake door is opened).

DTC DESCRIPTION
The A/C controller sets DTC B1209 if there is a short to power in the Intake potentiometer.

DTC Detecting Condition:




DTC DETECTING CONDITION

Specification:




SPECIFICATION

MONITOR SCANTOOL DATA
1. Connect scantool to Data Link Connector (DLC).
2. Engine "ON"




3. Monitor the "Intake Potentiometer" Parameter on the Scantool while operating Intake switch.
4. Are the DTC B1209 present and is parameter of "Intake potentiometer" fixed?
* Parameter of "Intake potentiometer" will be fixed at 100% (or any value above 90%), or 0% (or any value below 10%), if there is any fault in Intake potentiometer.

YES - Go to "Inspection" procedure.

NO - Fault is intermittent caused by poor contact in the sensor's and/or A/C controller's connector or was repaired and A/C controller memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.

TERMINAL AND CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals.
Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?

YES - Repair as necessary and go to "Verification of Vehicle Repair" procedure.

NO - Go to "Signal circuit inspection" procedure.

SIGNAL CIRCUIT INSPECTION
1. Check for short in harness.
1. Ignition "OFF"
2. Disconnect Intake potentiometer.




3. Measure resistance between terminal "6" and "5" of Intake potentiometer.

Specification : Approx. Infinity ohms

4. Is the measured resistance within specifications?

YES - Go to "Ground circuit Inspection" procedure.

NO - Check for short to power harness in signal harness. Repair as necessary and go to "Verification of Vehicle Repair" procedure.

GROUND CIRCUIT INSPECTION
1. Check for open in harness.
1. Ignition "OFF"
2. Disconnect Intake Potentiometer.




3. Measure resistance between terminal "7" of Intake Potentiometer and chassis ground.

Specification : Approx. 0 ohms

4. Is the measured resistance within specifications?

YES - Go to "Component Inspection" procedure.

NO - Check for open in ground harness. Repair as necessary and go to "Verification of Vehicle Repair" procedure.

COMPONENT INSPECTION
1. Check actuator motor.
1. Ignition "OFF"
2. Disconnect Intake Potentiometer.
3. Verify that the temperature actuator operates to the fresh position when connecting 12 V to the terminal "3"and grounding terminal "4".




4. Verify that the temperature actuator operates to the recirculation position when the connections are reversed.
5. Does the actuator work properly?

YES - Go to "Check potentiometer" procedure.

NO - Substitute with a known-good actuator and check for proper operation. It the problem is corrected, replace actuator and then go to "Verification of Vehicle Repair" procedure.

2. Check potentiometer
1. Ignition "ON"
2. Connect Intake potentiometer.




3. Measure voltage between terminal "7" and "6" of Intake potentiometer while operating Intake switch.

Specification : Refer to the specifications

Specifications: Voltage value of Intake potentiometer as a function of position of Intake.

4. Is the measured voltage within specifications?

YES - Check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.

NO
- Substitute with a known-good actuator and check for proper operation.
- If the problem is corrected, replace actuator and then go to "Verification of Vehicle Repair" procedure.

VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scantool and select "Diagnostic Trouble Codes (DTCs)" mode and then clear DTC.
2. Operate the vehicle and monitor the DTC on the scantool.
3. Are any DTCs present?

YES - Go to the applicable troubleshooting procedure.

NO - System is performing to specification at this time.