What it means
The ECM detects a circuit intermittent fault on the clutch position sensor b circuit. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Clutch position sensor B reports clutch position through a circuit the control module monitors during clutch and shift operation. P087E sets when that signal repeatedly drops out or becomes erratic rather than remaining stable as the clutch moves.
Common causes
Most likely first.
- Sensor connector not seated
- Noisy ground reference
- Connector with intermittent contact under vibration
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- Save freeze-frame data and review live sensor B data while slowly operating the clutch, looking for brief dropouts or sudden jumps.
- Check that the sensor B connector is fully seated and inspect its terminals and harness for looseness, corrosion, or vibration-related damage.
- Inspect the sensor's ground and reference connections for an unstable connection, then compare them with the manufacturer's specification.
- While monitoring the live signal, gently flex the harness and connector to locate an intermittent break or contact fault.
- If the wiring and connections remain stable, test sensor B through repeated clutch movements for intermittent output and replace it if it fails the manufacturer's specification.
Common fixes
- Fully seat and secure the sensor B connector.
- Repair loose, corroded, or damaged connector terminals.
- Repair intermittent wiring or ground connections and secure the harness against vibration.
- Replace clutch position sensor B if its signal drops out despite sound wiring.
Can I keep driving?
Avoid longer trips if the fault causes erratic shifts, and stop driving if shifts become unpredictable or limp mode engages. Intermittent position data can make the problem appear and disappear while still disrupting clutch and transmission control.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.