P0189 — Fuel Temperature Sensor B Circuit High Input
Drive with caution — fix soon.
What P0189 means
This code means the fuel temperature sensor B circuit is reading higher voltage than expected, which often means the signal is stuck high or the circuit is open. Typical causes include a failed sensor, an open or broken wire, or a poor connector. It's usually repaired by fixing the circuit or replacing the sensor after testing, and rarely involves major engine repair.
Common symptoms
- Check engine light is on
- Mild rough running or hesitation
- Slight decrease in fuel economy
- Occasional difficulty starting
- Sometimes no noticeable symptoms
Common causes
- Faulty fuel temperature sensor B
- Open or broken signal wire
- High resistance or loose connector
- Corrosion in the sensor circuit
- Engine control module input fault
Typical repair cost
$120 – $350
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0189 code?
Usually yes for short-term driving, since this is a sensor signal problem and not a mechanical failure. Get it diagnosed soon, particularly if you notice rough running or hard starts.
How much does it cost to fix a P0189 code?
Most repairs land between $120 and $350. Whether the fix is a new sensor or wiring repair is the main thing that moves the price up or down.
Is a P0189 code serious?
It's generally a low-to-moderate issue. It rarely strands you, but the faulty reading can affect fuel management, so it's smart to fix it before it causes other problems.
Does high input mean a broken wire?
High input often points to an open circuit or broken signal wire, but it can also be a failed sensor or bad connector. Testing the circuit is the only way to know for sure.