P2315 Ignition Coil F Primary Control Circuit Low
OBD2 Error Codes

P2315 Ignition Coil F Primary Control Circuit Low

P2315 Ignition Coil F Primary Control Circuit Low

OBD-II DTC Datasheet

Ignition coil F in primary control circuit low

What does P2315 mean?

This Diagnostic Trouble Code (DTC) is a generic transmission code and applies to many OBD-II vehicles (1996 and newer). This may include but is not limited to Mercedes, Ford, Mini, GMC, Sprinter, Chevrolet, etc. While general, the exact repair steps may vary depending on the model year, make, model and transmission configuration.

If your vehicle stores a P2315 code followed by a malfunction indicator lamp (MIL), it means that the powertrain control module (PCM) has detected an unexpectedly low voltage in the primary control circuit of the ignition coil, indicated by the letter F. Consult your manufacturer's manual to determine which circuit "F" is appropriate for your specific application.

The ignition coil primary circuits are the wires that supply battery voltage to the coil. Voltage is supplied through fuses, relays and various other sources. The high energy ignition boot, spark plug boot, or spark plug wire is NOT considered the primary circuit.

Typically, the ignition coil is supplied with battery voltage and ground. When the ground signal is interrupted (momentarily), the ignition coil emits a high voltage spark which also ignites the spark plug. The operation of a spark plug is a necessary component of an internal combustion engine. If the primary voltage at the ignition coil is insufficient, no high voltage surge will occur and the engine cylinder will not produce horsepower.

Typical individual cylinder (coils on the KS candle) ignition coils: P2315 Ignition Coil F Primary Control Circuit Low

What is the severity of this DTC?

When P2315 is saved, the cause should be diagnosed as soon as possible. The symptoms likely to accompany these codes usually require immediate attention.

What are some of the symptoms of the code?

Symptoms of a P2315 trouble code may include:

  • Engine misfire
  • Reduced engine performance
  • Reduced fuel efficiency
  • Other related codes
  • Fuel injector operation for the affected cylinder may be disabled by the PCM

What are some of the common causes for the code?

Reasons for this code may include:

  • Bad relay or blown fuse (fuse)
  • PCM failure
  • Open or short circuit in wiring or wire connectors (wildlife damage)
  • Defective ignition coil
  • Faulty camshaft or crankshaft sensor or wiring

What are some steps to troubleshoot the P2315?

You will need a diagnostic scanner, digital volt / ohmmeter (DVOM), and reliable vehicle information source to accurately diagnose the P2315 code.

You can save time and time by searching for Technical Service Bulletins (TSBs) that reproduce the stored code, vehicle (year, make, model, and engine) and symptoms found. This information can be found in your vehicle information source. If you find the right TSB, it can quickly fix your problem.

After you connect the scanner to the vehicle diagnostic port and get all stored codes and associated freeze frame data, write down the information (in case the code turns out to be intermittent). After that, clear the codes and test drive the car until one of two things happens; the code is restored or the PCM enters ready mode.

The code may be more difficult to diagnose if the PCM enters ready mode at this point because the code is intermittent. The condition that led to the persistence of P2315 may need to worsen before an accurate diagnosis can be made. If the code is restored, continue diagnostics.

You can get connector views, connector pinouts, component locations, wiring diagrams, and diagnostic block diagrams (related to the code and the vehicle in question) using your vehicle information source.

Visually inspect the associated wiring and connectors. Repair or replace cut, burnt, or damaged wiring. Wiring on top of the engine is often damaged by wildlife trying to keep warm in cold climates.

Use the DVOM to test the voltage and ground circuits on the ignition coil in question. If no voltage is found, check the system relays and associated fuses. Replace defective relays and / or blown (or otherwise defective) fuses as needed.

If voltage and ground are found across the coil, test the appropriate ground circuit at the PCM connector with the engine running. If a ground impulse is detected there, suspect an open circuit between the coil in question and the PCM. If no ground impulse is found there, suspect a faulty PCM or programming error.

  • The P2315 is often stored due to wiring damage caused by wild animals.

Related DTC discussions

  • 04 Mercedes CL203 SPORT COUPE, codes P2310, P2311, P2312, P2315Hi guys, my car is working fine. The problem is, it will start but won't start when it has been idle for more than four days. This occurs during very cold winter weather. I took it to the garage and replaced the starter relay. I drove the car for a month, and after four days of inactivity ... 

Need more help with the P2315 code?

If you still need help with DTC P2315, post a question in the comments below this article.

NOTE. This information is provided for informational purposes only. It is not intended to be used as a repair recommendation and we are not responsible for any action you take on any vehicle. All information on this site is protected by copyright.

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