Lexus IS Climate Control Panel Dead

I had a similar problem with my IS. By "error message", do you mean there's a code stored in the ECU (Engine Control Unit) or BCM (Body Control Module)? You really need to get the exact code read, which any generic OBD2 (On-Board Diagnostics II) reader can do, although a more advanced reader that can also read body codes is preferable here. Knowing the exact error code is the first step, but I agree, it sounds like a power supply or connection problem to the HVAC (Heating, Ventilation, and Air Conditioning) control panel. Did you try checking the relevant fuses?

Thanks for the reply! I haven't checked the fuses yet, I will look into that. I don't have a code reader, I will have to get one or see if a local shop can check it for me. When yours failed, was it completely dead like mine, or was it intermittent?

Mine was completely dead, yes. I spent some time troubleshooting wiring diagrams but eventually gave up and took it to a workshop. They diagnosed it as a faulty connector, and corrosion on the connector pins. The invoice states: "Cable or plug connection of the component defective." Cost me 95€ to get it fixed, so it wasn't a major repair, just annoying. Honestly, without proper diagnostic tools and electrical knowledge, chasing electrical gremlins in modern cars is a nightmare. Save yourself the headache and get it properly diagnosed.

Appreciate the insight. Sounds like I'm heading to the shop then! I was hoping for a simple fix, but I don't have the tools to properly diagnose it myself. Thanks again for sharing your experience; hopefully, it'll be something similar and won't break the bank!