P08DF: Shift Solenoid L Performance/Stuck Off

Functional fault of shift solenoid L: the TCM switches the valve on, but speed sensor data show that the intended clutch did not take up, so the valve acts as if stuck off. No manufacturer documents this code publicly. The detection logic is known from the analogue for solenoid A: Ford compares the obtained gear or shift pattern over three solenoid events, and GM's P0751 counts repeated slip of at least 400 rpm in a ratio window that does not match first gear, with the MIL after two trips. Typical causes are a valve jammed by debris, low line pressure or a leaking clutch circuit rather than wiring. CARB requires the check. P08E0 is the stuck-on fault. Expect flare or a missing gear.

Symptoms

• Check engine or transmission warning light on
• Engine flare between gears
• Gear missing or skipped

Most likely causes

• Shift spool jammed by debris
• Low line pressure or low fluid level
• Leak in the clutch circuit fed by the valve

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the fluid level and condition according to the manufacturer
2. Compare the reading with other engine data while varying the engine speed.
3. Check the transmission connector
4. Read the data with a transmission-compatible scanner
5. Measure the solenoid valve circuit
6. Leave opening the transmission to a specialized repair shop

Good to know

• It can trigger limp mode.
• It affects emissions.

What each character of P08DF means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• 8: Transmission
• DF: Specific fault in that system

Frequently asked questions

Can I keep driving with code P08DF?

Drive as little as possible and gently. If the transmission slips or stays in one gear, go slowly to a repair shop or call for a tow truck.

What causes code P08DF?

The most common causes are: shift spool jammed by debris; low line pressure or low fluid level; leak in the clutch circuit fed by the valve.

Related codes

• P08D6Shift Solenoid K Performance/Stuck Off
• P08DEShift Solenoid L
• P08E0Shift Solenoid L Stuck On
• P08E1Shift Solenoid L Electrical
• P0751Shift Solenoid A Performance/Stuck Off

Sources

• fordservicecontent.com: OBD Operations Summary Gasoline 2020 2023
• gsi.ext.gm.com: 16OBDG03 Transmission Diagnostics
• law.cornell.edu: 13 CCR 1968.2

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.