P0389 Mercedes-Benz Code - Crankshaft Position Sensor 'B' Circuit Intermittent
Quick Answer
The Crankshaft position sensor also known as the crank position sensor is an electronic device used in an engine to record the rate at which the crankshaft is spinning. Common causes include Faulty crankshaft position sensor, Crankshaft position sensor harness is open or shorted, Crankshaft position sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P0389 Mercedes-Benz indicates Crankshaft Position Sensor 'B' Circuit Intermittent.
- Common causes
- Common causes include Faulty crankshaft position sensor, Crankshaft position sensor harness is open or shorted, Crankshaft position sensor circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P0389 Mercedes-Benz Description
When the engine is running, the high and low parts of the teeth cause the gap with the sensor to change. The changing gap causes the magnetic field near the sensor to change. The change in the magnetic field cause the voltage from the sensor to change.
What are the Possible Causes of the DTC P0389 Mercedes-Benz?
- Faulty crankshaft position sensor
- Crankshaft position sensor harness is open or shorted
- Crankshaft position sensor circuit poor electrical connection
- Signal plate may be damage
- Starter motor may be faulty
- Starting system circuit
- Dead or weak battery
How to Fix the DTC P0389 Mercedes-Benz?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0389 Mercedes-Benz code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P0389 Mercedes-Benz code?
Need more information on how to fix the P0389 Mercedes-Benz code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0389 Mercedes-Benz code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P0389 Mercedes-Benz Code
1. What does the OBDII code P0389 mean on a Mercedes-Benz?
P0389 indicates an intermittent issue with the Crankshaft Position Sensor 'B' circuit, meaning the sensor's signal is not consistently reaching the engine control module (ECM).
2. What are the symptoms of a P0389 code in a Mercedes-Benz?
Common symptoms include engine stalling, difficulty starting, rough idling, reduced performance, and the Check Engine Light turning on.
3. What causes the P0389 code to appear in a Mercedes-Benz?
Possible causes include a faulty crankshaft position sensor, damaged or corroded wiring, loose electrical connections, or a malfunctioning ECM.
4. How serious is the P0389 code for my Mercedes-Benz?
It’s a serious issue because it can cause engine stalling or prevent the car from starting, potentially leaving you stranded.
5. Can I drive my Mercedes-Benz with a P0389 code?
Driving with this code is not recommended, as it may lead to further engine issues or leave you unable to start the car.
6. How do I fix the P0389 code on a Mercedes-Benz?
Start by inspecting and repairing any damaged wiring or loose connections near the crankshaft position sensor. If the issue persists, replace the sensor.
7. Where is the crankshaft position sensor located in a Mercedes-Benz?
The crankshaft position sensor is typically located near the engine’s crankshaft, often at the rear of the engine block or near the transmission bell housing.
8. How much does it cost to fix the P0389 code on a Mercedes-Benz?
Repair costs vary but typically range from $100 to $300, depending on whether the crankshaft position sensor needs replacement or if wiring repairs are required.
9. Can a dead battery cause the P0389 code?
A dead or weak battery is unlikely to cause this code directly, but electrical issues related to the battery or alternator could contribute to intermittent sensor signals.
10. How can I prevent the P0389 code from recurring in my Mercedes-Benz?
Regular maintenance, such as inspecting wiring and ensuring secure sensor connections, can help prevent this code from recurring.
Discuss the causes and fixes for P0389 Mercedes-Benz OBDII Code
Code P0389 Mercedes-Benz comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
