Error Code P1260 is defined as Theft Detected Vehicle Immobilized. This issue is usually caused by incorrectly programmed PCM (powertrain control module, also known as ECM or engine control module in other vehicle makes).

This error code is a generic trouble code, meaning it applies to all vehicles equipped with OBD-II system, especially vehicles made since 1996 up to present. Specifications on the definition, troubleshooting, and repairs, of course, vary from one make and model to another.

Definition

Error Code P1260 is set when the PATS (Passive Anti-Theft System) have determined a theft condition in the system which disabled the engine, or the engine will not start from a non-PATs key attempt. This error code is also a good indicator to check the PATs for error codes.

This code can also be set when there is a new IC (Instrument Cluster), IPS (Instrument Panel Cluster) or PCM installed, without the right programming for either of their modules if the device does not come with PATs.

Common Symptoms

The most common symptom for this code is the illumination of the Check Engine light on the dashboard. Also in many cases, since the vehicle is immobilized, the engine will not start.

Possible Causes

There are many possible reasons behind this error code, some of the most common causes include:

  • Wrongly programmed PCM
  • Wrongly programmed IC or IPC
  • Anti-theft system concern
  • Previous theft condition

How to Check

Try turning the key on and then leave it for a few minutes, or until the theft light stops flashing. Then start the vehicle. This will reset the system if the transceiver in the column is working.

If the ‘Theft’ light is still on or flashes and motor turns over but still don’t start, it is possible that the transceiver in the column is at fault. The PATs module is part of the PCM, if the transceiver cannot read the key, then it will disable the fuel ignition. In this case, you will have to take your vehicle to your dealer, or to the shop of a certified technician who will use an advanced scanner to access the PATs’ security portion. They can check the keys present, which will also tell them if the keys are still stored in the memory, as well as the transceiver to see if it is reading the keys.

If it is a case of a newly installed PCM, then there’s a good chance they erased the keys from the system. The PCM must be reprogrammed. In this case, you can ask for the help of a locksmith with a computer capable of reprogramming keys. Alternatively, you could also take your vehicle to your dealer.

How to Fix

As stated above, repairs for this error code usually revolves around reprogramming the PCM, which could only be done by your dealer, or by a certified technician.

Your dealer must reprogram the computer if the computer is capable of gaining 10-minute security access to the PATs system. If you cannot access your dealer, you can take your vehicle to a certified auto locksmith.