Error Code P1350 is defined as Ignition Control System.

This error code is a manufacturer-specific trouble code, meaning it does not apply to all vehicles makes. Rather, it applies only to specific vehicle makes, such as BMW, Citroen/Peugeot, Ford, GM, Lexus, Mercedes-Benz, Toyota, VW/Audi, and Volvo. Specification on the definition, troubleshooting, and repairs still vary from one make and model to another.


The ICM (Ignition Control Module) comes with an independent power and ground circuits. The circuits between the ICM and the PCM (Powertrain Control Module, also known as ECM or Engine Control Module in other vehicle makes) consists the following circuits:

  • Ignition control (IC) timing signal
  • IC timing control
  • Medium resolution engine signal
  • Low-resolution engine signal
  • Low reference
  • Camshaft position signal

The ICM sends 3X signals to the PCM, as well as control its timing advance during engine cranking. The timing advance changes to PCM controls after the following happens:

  • PCM receives the second 3X signal
  • The PCM applies 5V to the IC timing signal circuit

The CKP sync signal is monitored by the ICM when the engine is cranking. The CKP sync signal is then passed from the CKP sensor to the ICM on the CKP sensor 2 signal circuit. The CKP sync signal is used to determine the right cylinder pair and initiate the ignition coil firing sequence. The CKP sensor passes the 18X reference pulses to the ICM on the CKP sensor 1 circuit. These reference pulses are used for both ignition control and fuel injection. After the ICM receives both signals, the PCM receives the 18X and 3X reference from the ICM. The CMP and the CKP sensors share a 12-volt reference and low reference circuit. The CKP sensor consists of the following circuits:

  • 12V reference
  • Low reference
  • CKP sensor 1 signal
  • CKP sensor 2 signal

Common Symptoms

As with other error codes, this error code activates the Check Engine light and registers to the system.

Possible Causes

There are many factors for this error code to appear. Some of the most common possible causes are:

  • Faulty ICM
  • Open or shorted ICM
  • Poor electrical connections in the ICM

Note that the description, diagnosis, and repair for this error code in this guide are not applicable for all makes and models of vehicles that can have this error code. Again, P1350 is a manufacturer-specific trouble code, which means its definition, diagnosis, and repairs differ from one make and model to another. Make sure you check your manual or better yet, take your vehicle to your dealer or to a certified technician to have this error code properly addressed.