P1614 - FAULT CODE - OBD2

P1614 INFINITI, NISSAN: CHAIN OF IMMU-KEY

The immobilizer is an electronic device in the vehicle’s security system. It prevents the engine from running without the correct transponder key. Thus, it prevents the vehicle from being “hot-wired” after it has been entered, thus reducing car theft.

Recent 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 makes current flow in the key body. At the same time, it generates a binary code that is read by the ECM (Engine Control Module). If the ECM determines that the encoded key is current and valid, the fuel injection sequence is allowed.

The P1614 OBD2 fault code for Infiniti and Nissan is related to an immobilizer malfunction because the IMMU is not able to receive the ID signal. This is usually due to the use of an unprogrammed or defective key for the engine to start.

• Check Engine light ON.
• Impossible to start the engine.

These are the reasons to set the P1614 OBDII diagnostic code:

• The ignition key may have programming errors or be defective.
• The IMMU (Immobilizer Antenna) may be damaged.
• The ECM may be deficient.

The steps to resolve DTC P1614 OBD2 are:

• To begin the diagnosis, it is advisable to consult the TSBs.
• By using a scan tool, check if other DTCs in addition to P1614 are set. Diagnosis of these codes should be in the order shown on the tool.
• Disconnect the battery for at least 30 minutes. Then, try to start the engine with a properly programmed key, and check if the code is resolved. If not, reprogram the key.