P0315 OBD-II Trouble Code: Crankshaft Position System Variation Not Learned

What the P0315 code means

P0315 is the OBD-II generic code for a fault involving the crankshaft position system. The signals from the crankshaft are received by the powertrain control module. The sensor connected to the vehicle’s crankshaft stays in time by transmitting voltage signals to the powertrain control module. The voltage transmitted is compared to the reference voltage stored by the powertrain control module. If the difference between the signals exceeds a certain percentage, then the P0315 code is stored by the OBD-II system.

What causes the P0315 code?

The P0315 code has a number of common causes: * Faulty wiring around crankshaft position sensor * Faulty or corroded sensor connector * Faulty crankshaft position sensor * Faulty powertrain control module * Damaged crankshaft * Broken timing belt

What are the symptoms of the P0315 code?

When the P0315 code appears, the Check Engine light will illuminate on the dashboard after a short while. Depending on the cause of the P0315 code, the symptoms exhibited by the vehicle will vary. If the cause of the problem is electrical, the symptoms will include the Check Engine light on the dashboard and possibly a drop in fuel economy. If the problem causing the code is mechanical, then the engine will be exhibiting systems like a rough idle and poor performance.

How does a mechanic diagnose the P0315 code?

The P0315 code will be diagnosed by a qualified technician with an OBD-II scanner capable of viewing the factory readings from the OBD-II system. This will allow the technician to not only view the trouble codes that have been stored, but to see the time the issues occurred. This information will be recorded and the codes will be reset. The vehicle will then be taken for a test drive. If the code appears once again during the drive, then it will confirm that the issue is not just an intermittent one.

Once the issue is confirmed to be the P0315 code, the technician will inspect the crankshaft position sensor and the wiring and circuitry associated with the sensor.

Common mistakes when diagnosing the P0315 code

With problems like the P0315 code that can have a mechanical or electrical origin, electrical problems are often diagnosed as mechanical problems and vice versa. This can be a very expensive mistake if the problem lies with an electrical connector and a major component like the crankshaft is repaired or replaced unnecessarily.

How serious is the P0315 code?

The P0315 code is a very serious trouble code. The code itself can result in the engine being rendered unable to start. The code can be caused by the failure of major components within the engine. If the code does not render the engine unable to start, the problems that caused the code to be stored can negatively affect fuel economy and performance. If the P0315 code appears, have it assessed by a qualified technician as soon as possible.

What repairs can fix the P0315 code?

The most common repairs to address the P0315 code are as follows:

• Repair or replace wiring harness around crankshaft position sensor
• Repair or replace crankshaft position sensor
• Repair or replace crankshaft or related components
• Repair or replace timing belt
• Repair or replace powertrain control module

Additional comments for consideration regarding the P0315 code

In some instances, the crankshaft position sensor and associated wiring is damaged during the replacement of a broken timing belt. This damage can cause the P0315 code to appear.

Need help with a P0315 code?

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