What it means
Same as P071B on switch B. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
How it works
Transmission mode switch B reports a selected mode or selector state to the control module. P071E sets when the module sees switch B's signal below its expected range, consistent with the signal being pulled toward ground.
Common causes
Most likely first.
- Signal shorted to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
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
- Read freeze-frame and live data for mode switch B to confirm the low signal and identify the selector position and conditions when it occurs.
- With the vehicle safely parked, move the selector through its positions and check whether switch B's reported state matches each selection.
- Inspect switch B's connector and harness for water, corrosion, pushed-back pins, or insulation worn through to ground.
- Watch switch B live data while gently moving the harness to see whether a low signal appears or changes at a particular spot.
- Use the wiring diagram to test switch B's signal for a short to ground and check connector contact and switch operation against the manufacturer's specification.
Common fixes
- Clean and secure corroded or loose switch B connector terminals.
- Repair chafed switch B signal wiring that is contacting ground.
- Repair damaged connector seals or terminals that allow moisture or poor contact.
- Replace mode switch B if its signal remains low with the wiring verified.
Can I keep driving?
Avoid relying on the transmission's mode selection if shifting becomes harsh, delayed, or incomplete; the transmission may enter a protective gear strategy. Stop driving if it slips or shifts unpredictably.
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.