B2797 2018 Toyota RAV4 Code - Communication Malfunction No. 1 Immobilizer System

Code B2797 indicates a "Communication Malfunction No. 1" in the immobilizer system, meaning there’s an issue with communication between the key transponder and the engine control module (ECM).

Common symptoms include the engine not starting, the immobilizer warning light staying on, or intermittent starting issues.

The most common causes include a faulty key fob or transponder, damaged wiring or connections in the immobilizer system, or a malfunctioning ECM or immobilizer control module.

Yes, a low or dead key fob battery can disrupt communication between the key and the immobilizer system, potentially triggering this code.

Diagnosis involves checking the key fob functionality, inspecting immobilizer system wiring and connections, testing the immobilizer antenna coil, and using a scan tool to verify communication signals.

In some cases, reprogramming or re-pairing the key to the immobilizer system can resolve the issue if the key’s data has been corrupted or erased.

No, it’s not safe, as the vehicle may fail to start or shut down unexpectedly due to immobilizer system issues.

Repair costs vary but typically range from $100 to $500, depending on whether the key fob, wiring, or immobilizer module needs replacement or reprogramming.

You can clear the code temporarily with an OBDII scanner, but the problem will return unless the underlying issue is resolved.

While some repairs, like key reprogramming, may require a dealership or specialized locksmith, many issues can be diagnosed and repaired by a qualified mechanic with the right tools.