P1613 - FAULT CODE - OBD2

P1613 INFINITI, NISSAN: ECM INT CIRC-IMMU

The immobilizer is an electrical device that is installed in vehicles with the purpose of preventing the operation of the car without using the proper key. With this device, the car does not engage hot once the entry is achieved.

A microcircuit is located inside the key. This induces through an electromagnetic field a current flow in the key body, and this action creates an ID that is unique and is read by the ECM (Engine Control Module). If this controller determines that the coded key is valid and current, it is authorized to start the injection process.

In the immobilizer system, known in Infiniti cars as IVIS (Infiniti Vehicle Immobilizer System) and in Nissan as NATS (Nissan Anti-Theft System), there is the NATS ignition key, a NATS antenna amplifier, the BCM or IMMU, the ECM and an indicator lamp that serves as a security element.

The P1613 OBDII fault code is set when a malfunction is detected by the ECM internal circuit of the IMMU communication line.

• Check Engine light illuminates.
• Unable to start the engine.

The reasons for the DTC P1613 OBD2 are as follows:

• Ignition keys may not be programmed or have been damaged.
• The IMMU may have been damaged.
• The Engine Control Module may be faulty.

Follow the steps outlined below to troubleshoot the P1613 OBDII diagnostic code:

• Consult the Technical Service Bulletins.
• With a scan tool, it is necessary to check if additional DTCs to P1613 are configured, related to immobilizer problems. If such codes are found, you must diagnose them following the order indicated by the tool.
• Disconnect the battery for at least 30 minutes. Then, start the engine using a programmed key. If the fault is not solved, it is necessary to reprogram the keys and erase the code.