P0339 - Crankshaft Position Sensor A

The P0339 trouble code gets stored in the engine control modules’ trouble code memory when there is a problem with the circuit to the crankshaft position sensor A.

This can be caused by a few things, and in this article, I will go through everything you have to know about the P0339 sensor.

Code P0339 Definition

Crankshaft Position Sensor A – Circuit Intermittent

What does the P0339 code mean?

The P0339 error code indicates that the engine control module received an intermittent high signal (voltage) or an error signal from the crankshaft sensor ‘A.’ The function of the crankshaft sensor is to read where the crankshaft is in the cycle.

It is used to know when the injectors and ignition coils need to be ignited. The RPM will also be displayed on your dashboard by the crankshaft sensor.

P0339 Trouble Code Symptoms

The most common symptoms of the P0339 code are no start condition, check engine light, sudden engine stall, and performance issues.

Here are some other symptoms of the P0339 code:

Hard starting condition
Sudden engine stall
Check Engine light
Engine Performance Issues
Dead RPM meter on the dashboard while cranking

Causes of the P0339 Code

The most common cause of the P0339 code is a faulty crankshaft sensor. There could also be problems with the wirings or connectors.

Code P0339 could be caused by any of the following issues:

Faulty or damaged crankshaft position sensor (most common)
Wiring issue between the crankshaft sensor and engine control unit, shorted or open circuit
Faulty connector to the crankshaft sensor, corrosion
A faulty engine control unit (rare)

How serious is the P0339 Code?

Serious – The car engine needs the crankshaft sensor for the engine to run. This means that a faulty crankshaft position sensor can make your car stall and stop completely at any moment.

Therefore, I recommend fixing the P0339 code as fast as possible. It is often pretty easy and cheap to repair this trouble code.

What repairs can fix the P0339 code?

Clean the connector to the crankshaft sensor
Repair the wirings between the ECM and crankshaft sensor
Replace the crankshaft sensor
Replace the engine control unit
Charge your car battery or replace the car battery

Common P0339 Diagnosis mistakes

The most common diagnosis mistake of the P0339 code is thinking there is a problem with the camshaft timing and beginning the troubleshooting there. This P0339 says there is an electric circuit problem with the crankshaft sensor, not a timing problem.

Another common problem is replacing the crankshaft sensor without checking the wirings or connector plugs.

Recommended Tools for Diagnosis

Diagnostic OBD Scan Tool
Multimeter
Basic Hand Tools
Auto Repair Manual
Electrical Contact Cleaner

How to diagnose the P0339 Trouble Code

This is a guide on how you can diagnose the P0339 code easily. You may need some special tools to complete this diagnostic procedure.

Connect an OBD2 code scanner and check for other related trouble codes.
Visually inspect the crankshaft sensor. Unplug the connector and check for corrosion.
Find the ohm measure values for the crankshaft sensor from your repair manual. Measure the sensor and replace it if there is an open circuit or a false signal.
You can also check the crankshaft position sensor signal with an oscilloscope if you have access to one.
Remove the connector plug from the engine control unit, and measure the same values to the crankshaft position sensor from the engine control unit’s connector plug. Repair wirings if any issues are found.
Replace the crankshaft sensor even if your test values were okay. This is an intermittent trouble code, which can mean that the problem is not occurring right now.
Replace the engine control unit if everything else seems good.

Estimated Cost of Repair

Here are some common repairs related to the P0339 trouble code. The prices include labor and part costs, but do not include diagnostic costs.

Crankshaft position sensor replacement – 50$ to 150$
Crankshaft position sensor wiring repair – 20$ to 70$

How do I fix code P0339?

To fix the P0339 trouble code, you’ll need to find out what’s causing the problem with the circuit to the crankshaft position sensor. This might be the sensor itself, which can be faulty, but other defects may also trigger this code. Other possibilities include damaged or dirty connectors, broken wiring, and sludge buildup on the sensor’s surface. Some engines have a reluctor ring from which the crankshaft position sensor picks up its signal, and it may get corroded or bent out of shape. All of this should be ruled out when troubleshooting the P0339 code.

Is It Safe To Drive With Code P0339?

No. Driving with the P0339 trouble code is anything but safe, especially for longer trips. This code is triggered when the ECU doesn’t receive a correct signal from the crankshaft position sensor. This is the most vital of all sensors in a modern engine, as the data it provides is used to adjust the fuel and ignition timing. A malfunctioning crankshaft position sensor could cause various engine running issues, such as hard starting, misfiring, or stalling.

How Do You Clear Code P0339?

An OBD2 scanner is needed to clear the P0399 code, which you’ll use to access the vehicle’s diagnostic memory and delete all stored codes. This, however, should be the final step after you’ve diagnosed and fixed what triggered the code in the first place. Otherwise, the trouble code, as the problem itself, will just keep coming back.

What happens if you don’t fix a bad crankshaft sensor?

If you drive with a bad crankshaft sensor, you may get stranded at the side of the road, or your car may even cut out. The engine will not run if the ECU doesn’t know when to trigger the ignition and fuel injectors. And for that, it needs a correct signal from the crankshaft position sensor. Even if the car seemingly runs fine, it may stall while driving, which can lead to an accident. In addition, a malfunctioning crankshaft position sensor can prevent the engine from starting.

The P0339 trouble code is triggered when the ECU detects a problem with the crankshaft position sensor’s signal. This is the most vital of all engine sensors, as the data it provides is used to adjust ignition and fuel timing.

If it fails, the car will not start or may cut out while driving. Even if this doesn’t happen, a malfunctioning crankshaft position sensor may still cause various running issues, such as a misfire or poor engine performance. Apart from the sensor itself, the problem may be caused by broken wiring and connectors or sludge buildup on the sensor’s surface.