PATS Is Disabled (Check Link Between PATS And Transponder)
Your car's security system (PATS) can't communicate with your key's transponder chip, like a lock that can't read your key's unique pattern. The vehicle won't start because it can't verify the key is authentic.
The PATS module sends a signal to the transponder in the key and expects a valid coded response back within a specific time window. If no response or an invalid code is received, the ECU disables fuel injection and ignition to prevent unauthorized starting. The system monitors signal strength and response integrity.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Transponder Response Signal | Valid coded signal received within 100-200ms | No response, weak signal, or invalid code detected |
| PATS Module Communication Link | Active two-way communication established | Communication timeout or link failure |
Code B1682 is a low-severity fault. Your vehicle is generally safe to drive to a workshop for diagnosis. However, do not ignore it indefinitely — low-severity codes often indicate developing problems that become expensive if neglected. Book a diagnostic appointment within 2–4 weeks. If you notice any additional symptoms (rough running, power loss, unusual smells), treat it as higher priority.
Once the fault is repaired, B1682 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.