What it means
Shift fork A position signal drops out intermittently. Loose connector or vibration-sensitive wiring.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Shift fork A moves a transmission selector, while its position sensor lets the TCM track the fork during gear changes. P2835 sets when the fork A signal drops out intermittently, so the TCM sometimes loses a reliable position reading.
Common causes
Most likely first.
- Connector not seated
- Harness chafing intermittently shorts the wire
- 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
- Record freeze-frame data and check whether P2835 is current or stored, then monitor live fork A position data for dropouts during the same operating conditions.
- Inspect and reseat the fork A sensor connector, checking for loose locks, corrosion, moisture, or terminals that have backed out.
- Examine the fork A harness along its route for chafing, pinching, or damage that could open or short the signal intermittently.
- With the vehicle safely stationary and following the manufacturer's procedure, gently move the accessible harness and connector while watching the live signal for interruptions.
- If the wiring remains stable, test the fork A sensor and its connector contact under the conditions specified by the manufacturer.
Common fixes
- Reseat and secure a loose fork A sensor connector.
- Clean corroded terminals or repair poor terminal contact.
- Repair chafed or vibration-sensitive wiring in the fork A circuit.
- Replace the fork A position sensor if its signal drops out with sound wiring and connections.
Can I keep driving?
If the fault causes missed shifts, slipping, or limp mode, avoid driving except as needed to reach a safe stopping place; the transmission may lose track of gear engagement. Have the vehicle recovered if shifts are unpredictable.
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.