B2418
B2418Component Location:
General Description
Temperature control actuators are installed at driver side, passenger side, and rear vent. Control switches and rear vent duct switch will operate actuators, that will regulate temperature control position and discharge air temperature.
DTC Description
The ECM sets DTC B2418 if there is short to power harness in signal haness of the RR vent Temp Potentiometer
DTC Detecting Condition:
Schematic Diagram:
Specification:
Monitor Scantool Data
1. Connect scantool to Data Link Connector (DLC).
2. Engine "ON".
3. Monitor the"REAR AIR MIX DOOR" parameter on the scantool while changing position of air mix potentiometer.
4. Are the DTC B2418 present and is parameter of "REAR AIR MIX DOOR" fixed ? Parameter of "REAR AIR MIX DOOR" will be fixed at 100% (or any value above 94%), if there is any fault in RR VENT Temp Potentiometer.
YES - Go to "Inspection & Repair" procedure.
NO - Fault is intermittent caused by poor contact in the sensor's and/or ECM's connector or was repaired and ECM 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 Vehicle Repair" procedure.
NO - Go to "W/Harness Inspection" procedure.
Signal Circuit Inspection
1. Check for short in harness
1. Ignition "OFF".
2. Disconnect RR VENT Temp actuator.
3. Measure resistance between terminal "5" and "4" of RR Vent Temp Potentiometer
Specification : Approx. 0 ohms
4. Is the measured resistance within specifications?
YES - Go to "Component Inspection" procedure.
NO - Check for short to power harness in signal harness. Repair as necessary and go to "Verification Vehicle Repair" procedure.
Ground Circuit inspection
1. Check for open in harness
1. Ignition "OFF".
2. Disconnect RR VENT Temp Actuator.
3. Measure resistance between terminal "6" of RR Vent Temp Actuator and terminal "14" of A/C Control Unit
Specification : Approx. Infinite ohms
4. Is the measured resistance within specifications?
YES - Go to "Component Inspection" procedure.
NO - Check for short to ground in signal harness. Repair as necessary and go to "Verification of Vehicle Repair" procedure.
Component Inspection
1. Check actuator
1. Check actuator motor
1. Ignition "OFF"
2. Disconnect RR Vent Temp Potentiometer.
3. Verify that the temperature actuator operates to the hot position when connecting 12 V to the terminal 1 and grounding terminal 3
4. Verify that the temperature actuator operates to the cool position when connecting in the reverse.
5. Dose the actuator work properly?
YES - Go to "Check potentiometer" 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.
2. Check actuator potentiometer
1. Ignition "ON".
2. Disconnect RR Vent Temp Potentiometer.
3. Measure voltage between terminal "5" and "6" of RR Vent Temp Potentiometer while operating the temperature switch
Specification : Refer the specifications in fig 3)
4. Is the measured voltage within specifications in fig 3) ?
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.