What does it mean?
B1000 is a Body (airbags, seat belts, body electronics) fault code. It indicates: A/C Switch Request Input Circuit/Performance .
Symptoms
- A/C does not engage when the button is pressed, or engages on its own without a request
- A/C button indicator light does not illuminate
- Compressor clutch never cycles and only ambient temperature air comes from the vents
- Engine idle does not rise as it normally does when the A/C is switched on
- Windows take much longer to demist because the compressor is not running
- Climate related warning or message on the display
Likely causes
- Failed A/C request switch or worn contacts inside the climate control panel
- Open, shorted or high-resistance wiring between the switch and the module
- Corroded, loose or partially seated connector at the climate control head
- Blown fuse feeding the switch or the control panel
- Poor ground for the climate control panel
- Faulty input circuit inside the receiving module
- Aftermarket accessories spliced into the A/C request circuit
- Refrigerant pressure switch inhibiting the request so it never reaches the module as expected
How to fix it
- Press the A/C button while watching the request status in live data to see whether the module registers it
- Check the fuse that feeds the climate control panel and the switch circuit
- Inspect the connector at the panel for bent, corroded or backed-out terminals
- Measure switch continuity or resistance in the pressed and released positions
- Check circuit continuity from the switch to the module and confirm the panel ground
- Verify refrigerant charge and the pressure switches before condemning any electrical part, since a low charge can block the request
- Repair the wiring or replace the switch/control panel, and replace the module only if its input pin is proven dead