This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.
P0315 is an OBD-II Code that refers to Crankshaft Position System Variation Not Learned
A P0315 code is the result of the ECM (Engine Control Module) receiving a signal from the sensor connected to the vehicle’s crankshaft. This in turn stays in time by transmitting voltage signals to the powertrain control module. The powertrain control module compares the voltage transmitted to the stored reference voltage. This signal is then transmitted to the ECM stating that the timing of the camshaft and crankshaft are not within specifications.
Common causes for this code include:
- Bad Crankshaft Position Sensor
- Open in Crankshaft Position Sensor wire(s)
- Short to ground on Crank Shaft Position sensor wire(s)
- Broken timing belt
- Damaged crankshaft
- A defective powertrain control module
The symptoms of a P0315 code are:
- Check light will turn on
- A possible drop in fuel economy
- Engine cranks but does not start
- Lack of power when accelerating from a stop or when driving up hills/inclines
To diagnose a P0315 DTC code, a technician would:
1. Verify the code is present using an OBD-II scanner
2. Look up the freeze frame data for this particular code on the same vehicle
3. Observe that there are no engine or transmission lights illuminated
4. Have the driver start and accelerate the engine to 4000 rpm then let it idle again
5. Note that if any of these conditions happen during diagnosis, be sure to consult a service manual for specifications.
The following are common mistakes when diagnosing the trouble code P0315:
Electrical difficulties are frequently mistaken for mechanical ones, and vice versa, since they may originate from either the electrical or mechanical systems. If the issue is with an electrical connection but a crucial component like the crankshaft is fixed or replaced unnecessarily, this can be very costly.
How serious is this?
A P0315 code is a serious and potentially dangerous issue. This is because the timing between the camshaft and crankshaft will not be in sync, which can cause increased emissions and increased fuel consumption. In addition, this can lead to a misfire or other issues with the crankshaft position sensor. In a worst-case scenario, it may also lead to a breakdown of the engine.
What repairs can fix the code?
The following are solutions that may fix this problem:
- Check, clean and tighten all electrical connections for the crankshaft position sensor to ensure they are secure
- Replace or repair the timing belt as needed.
- Replace or repair faulty wiring or connectors
- Replace damaged components such as the camshaft drive belt if it is broken. This will require partial disassembly of the engine. If this fails, repair may be required
- Replace the entire crankshaft if it fails.
- Repair or replace low reference voltage problems in the powertrain control module
A P0315 is related to and may be accompanied by the following codes:
- P0316 – Crankshaft Position Sensor A Circuit High
- P0317 - Crankshaft Position Sensor A Circuit Intermittent/Erratic Signal
- P0318- Crankshaft Position Sensor B Circuit Malfunction
- P0321- Camshaft Position Sensor “A” Circuit (Bank 1)
- P0322- Camshaft Position Sensor "A" Circuit Range/Performance (Bank 1)
- P0430- HO2S Heater Control Circuit (Bank 1 Sensor 1)
How much does it cost to fix the P0315 code?
The repair cost of a P0315 code varies from one vehicle make and model to another. In general, though, the average cost is between $400-500 for parts and labor.
In conclusion, the P0315 code is a very serious issue. It is related to and may be accompanied by several other codes, all of which can cause serious problems if not repaired. If you do not address this issue promptly, extensive engine damage can occur. To avoid wasting money on unnecessary repairs, be sure to consult a service manual for specifications and tolerances if you are not certain of the diagnosis.
A PDF VERSION OF THIS ARTICLE FOR LATER