P0389 code meaning
Crankshaft Position Sensor B Circuit Intermittent
Powertrain system Generic code P03xx codes Check engine light
What P0389 means
Some engines have a second crankshaft sensor or a second track on the tone wheel – GM's 3.4/3.5/3.8-litre V6 use the low resolution track of a dual Hall sensor, the Honda 3.5-litre in the Saturn Vue Redline a second sensor – which the engine module checks against sensor A or the camshaft. By its J2012 name P0389 means the signal of sensor B drops out for moments or becomes erratic – missing or extra edges – without staying permanently low or high. Such faults are typically found by counting pulses against sensor A or the camshaft, as GM's 3.8-litre V6 and the Honda engine do; both, however, report the result under P0385/P0386, and no manufacturer document available to us uses P0389. The description therefore follows the J2012 name, these component sources and CARB. Typical causes are a loose contact, a broken wire and interference.
P0389 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P0389
- Check engine light on, possibly only after several trips
- Occasional stalling or jerking
- Sporadic starting problems
Common causes of P0389
- Most likelyLoose contact or corrosion at the sensor B connector
- Most likelyWire break or chafing that appears with engine movement
- PossibleElectrical interference (add-on devices, routing near ignition or relays)
- PossibleTone wheel damaged or dirty, air gap too large
- PossibleSensor faulty, temperature-dependent
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Crankshaft position sensor bCrankshaft tone wheelSensor wiringEngine control module
What each part of P0389 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 3 | Area: ignition system or misfire. |
| 89 | The exact fault in that area. |
What to do next
- Note P0389 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0389
What does P0389 mean?
P0389 means "Crankshaft Position Sensor B Circuit Intermittent". Some engines have a second crankshaft sensor or a second track on the tone wheel – GM's 3.4/3.5/3.8-litre V6 use the low resolution track of a dual Hall sensor, the Honda 3.5-litre in the Saturn Vue Redline a second sensor – which the engine module checks against sensor A or the camshaft. It is a generic code, so it means the same on every make.
Is it safe to drive with P0389?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P0389 fail an emissions test?
Yes, it can. P0389 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0389 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P0389 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.