P08E0: Shift Solenoid L Stuck On

What it means

Shift solenoid L stays activated when commanded off. Gear element remains engaged.

At a glance

• Usually lights the check-engine light
• The engine or gearbox may go into limp mode

How it works

Shift solenoid L is an electrically controlled valve that routes hydraulic pressure to a gear element in the transmission. The TCM monitors its command and the resulting circuit and transmission response. This code sets when solenoid L remains active after the TCM commands it off, leaving the gear element it controls engaged.

Common causes

Most likely first.

1. Solenoid spool stuck open
2. TCM output driver stuck on
3. Carbon or debris buildup preventing free movement

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

1. Save freeze-frame data and check whether the TCM commanded solenoid L off when the fault occurred.
2. Review live data for solenoid L command and available gear or pressure feedback to see whether its gear element remains engaged.
3. Inspect the solenoid L wiring and connector for damage, fluid contamination, corrosion, or loose pins.
4. Test solenoid L and its control circuit against the manufacturer's specifications to distinguish a sticking valve from an electrical fault.
5. If circuit testing passes, inspect the valve body for a stuck-open solenoid L spool or debris restricting movement.
6. Check the TCM output only if testing indicates solenoid L is still being energized after an off command.

Common fixes

• Repair damaged or contaminated solenoid L wiring and connector terminals.
• Clean or service the valve body if debris is preventing solenoid L from moving freely.
• Replace solenoid L if its valve spool sticks or it fails testing.
• Repair the TCM output driver if it continues to energize solenoid L when commanded off.

Can I keep driving?

Avoid driving if shifts are harsh, slipping, or the transmission stays in one gear; the engaged element can cause additional wear or damage. If the vehicle enters limp mode or behaves unpredictably, stop driving and arrange assistance.