Error code

OBD2 P0385

OBD2P0385
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

Crankshaft Position Sensor 'B' Circuit.

Severity

moderateThe vehicle may be drivable but with reduced performance and potential starting issues.

Summary

P0385 indicates a malfunction in the crankshaft position sensor B circuit, which is crucial for determining engine speed and position.

Symptoms

  • No-start or start-stall conditions
  • Hard starting
  • Rough idle
  • Poor acceleration

Common Causes

  • Faulty crankshaft position sensor B
  • Wiring issues between the ECU and crankshaft position sensor B
  • Improper installation of the crankshaft position sensor B
  • Electrical interference from an alternator phase problem (Ford trucks/Mustang GT)
  • Damage to wiring harness due to pests or age

Diagnosis

  1. Visual inspection of all connectors and wiring harness for damage
  2. Sensor resistance check to identify open or short circuits
  3. Signal verification using a digital volt-ohm meter (DVOM) while cranking the engine

Fixes

  • Replace faulty crankshaft position sensor B

FAQ

What can cause P0385?

Common causes include a faulty crankshaft position sensor, wiring issues, improper installation, electrical interference from an alternator phase problem (Ford trucks/Mustang GT), and damage to the wiring harness.

How do I diagnose P0385?

Diagnosis involves visual inspection of connectors and wiring, checking sensor resistance for open or short circuits, and verifying signal using a DVOM while cranking the engine.

View source

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.

More OBD2 codes

All OBD2 codes →Search more codes →