B1015-Rear Defrost Switch Request Input Circuit/Performance: Notes
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For a complete wiring diagram, refer to appropriate SYSTEM WIRING DIAGRAMS information.
Theory of Operation
The HVAC A/C Heater Control contains various switches and knobs that are used to change the systems operation. Many of the switches are momentary switches which are normally open or in the Off position and the status changes when the switch button or knob is pushed or turned. An active Diagnostic Trouble Code (DTC) indicates that the switch is stuck in an On position. A stored DTC indicates that the switch was stuck in a On position for more than two minutes but has since returned to its normal state of Off.
- >>When Monitored:<< With the ignition on.
- >>Set Condition:<< If the Electric Back light (EBL) Electronic Rear Defrost switch is stuck in an On position for more than two minutes. This DTC has a de-maturing time of one second. If the DTCs status changes from active to stored, the DTC will stay in memory for 100 ignition cycles.
| Possible Causes |
|---|
| OBJECT HOLDING SWITCH IN AN ON POSITION |
| A/C HEATER CONTROL |
Always perform the HVAC Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to HVAC .