The immobilizer is an electronic device in the vehicle security system. Prevents the engine from running without the key correct transponder. In this way, it prevents the vehicle from “hot” after having entered it, thus reducing car theft. Code P1614
Newer models of the immobilizer system use rolling codes or advanced cryptography so that the code cannot be copied from the key or control module. A microcircuit in the key is initiated by an electromagnetic field that causes current to flow in the body of the key.
At the same time, it generates a binary code which is read by the ECM (Engine Control Module). If the ECM determines that the coded key is current and valid, the fuel injection sequence is allowed.
The P1614 OBD2 fault code for Infiniti and Nissan is related to a malfunction of the immobilizer because the IMMU is not able to receive the identification signal. This is usually due to the use of an unprogrammed or defective key to start the engine.
What does the P1614 code mean?
Although this guide will cover the code P1614- “IMMU-KEY string”, in regards to Nissan and Infiniti applications, note that some sources also list the P1614 code as “Immobilizer Control Module/Module Coding Plug Communication – No Signal.” And although Nissan’s definition is the most common, other brands may have different definitions of P1614, and this guide will not apply.
Reads: Error Code P1101 – Mass Air Flow Sensor Out of Self-Test Range
Typically this code is activated because a damaged or unregistered key has been used in an attempt to start the engine. It means that the IMMU cannot read the key identification signal. In other cases, it means that something more serious is wrong with the immobilizer or the ECM itself.
What are the common causes of code P1614?
When an unregistered key is used at least five consecutive times, the immobilizer causes the system to lock. This prevents the vehicle from being started at all. This code is also activated to inform you of the problem.
Both the Nissan anti-theft system and the Infiniti vehicle immobilizer system have this immobilizer function. It consists of the following components
The immobilizer is installed on the car to prevent theft. It is an electronic device that cuts off the engine when the wrong key is present. This prevents thieves from bridging the car after they have entered.
The correct key microcircuit is activated by a small electromagnetic field that provides current flow to the key body. This rotates and outputs a binary code that is unique to your system. This is read by your car’s ECM. Once the ECM determines that you have the appropriate coded key, the ECM turns and activates your fuel injection system so the vehicle can start.
If you are using the proper wrench and get a code P1614it is likely a faulty immobilizer unit or ECM causing the problem instead.
What are the symptoms of code P1614?
How do you fix the P1614 code?
Questions and answers
Q: Hello..who can help me what to do on the Nissan Murano with the code p1614?
A: The P1614 fault code occurs because there is a problem with the Nissan anti-theft system. Typically this code is activated because a damaged or unregistered key FOB was used in an attempt to start the engine. It means that the IMMU (immobilizer control unit) cannot read the key identification signal.
In other cases, it means that something more serious is wrong with the immobilizer or the ECM itself. Check the fuse; If OK, try a new battery in the FOB. If the FOB is defective, you will have to purchase a new one and register it at a locksmith shop or Nissan dealership.
Q: I just changed the alternator on my 01 Sephia. I get error code P1614 and the transmission starts in 2nd gear when I start it. Just manually shift from 1st to 2nd. Suggestions?
A: You may have already moved on from this but I can tell you that your error code P1614 is for “MIL Request Circuit Voltage High.” I’m not sure but I think MIL stands for “Malfunction Indicator Light or Lamp”? I’m not quite sure what it means, but I’m sure someone on the site does.
Transmission – You say you didn’t have any problems with the transmission until you changed the alternator. I don’t see how the alternator could be related.
If you want to know other articles similar to Error Code P1614 – IMMU-KEY String (Nissan, Infiniti) you can visit the category Fault Codes.