P0868: Transmission Fluid Pressure Low (Meaning, Causes, Fixes)
What P0868 means
Automatic transmissions use hydraulic fluid pressure to apply clutches and shift gears. A transmission fluid (line) pressure sensor reports that pressure to the transmission or engine computer. RepairPal says P0868 sets when the transmission control module (TCM) sees an incorrect, low signal from the fluid pressure sensor. The Chrysler factory service manual for the 42RLE transmission (2007 Jeep Wrangler JK) gives a specific test: while driving in a forward gear, the computer compares actual line pressure to the pressure it wants, and sets P0868 if actual pressure is more than 10 psi below desired. That 10 psi figure comes from the Chrysler manual and may differ on other makes. Its opposite is P0869 (transmission fluid pressure high), per KBB.
Severity: can I keep driving?
Stop and fix promptly
Treat it as serious. RepairPal rates P0868 Urgent and KBB calls it extremely serious, because low fluid pressure affects how the transmission shifts and can lead to overheating and transmission damage. Avoid long drives. If the transmission slips, won't shift out of first, overheats or goes into limp mode, have it checked before driving further, or have it towed.
Common symptoms
- Check engine light on (KBB)
- Transmission may not shift properly, gears slipping or not shifting at all (RepairPal, KBB)
- Transmission overheating (KBB)
- Limp mode on some vehicles, which limits gears and speed to protect the transmission (KBB)
- Increased fuel consumption (RepairPal)
Likely causes
Roughly most to least common, based on the sources below. Your vehicle may differ.
- Low transmission fluid level, often from a leak (RepairPal, KBB, Chrysler service manual)
- Dirty or contaminated transmission fluid (KBB)
- A faulty transmission fluid (line) pressure sensor (RepairPal, KBB, Chrysler service manual)
- Damaged wiring, including an open or shorted 5-volt sensor supply or a shorted pressure control solenoid circuit (RepairPal, KBB, Chrysler service manual)
- A cracked, plugged or misinstalled transmission oil filter, or a stuck main pressure regulator valve (Chrysler service manual)
- A failing transmission oil pump or other internal transmission failure (KBB, RepairPal, Chrysler service manual)
- A faulty TCM or PCM, which KBB calls extremely uncommon (RepairPal, KBB, Chrysler service manual)
Diagnostic steps you can do
Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.
- Read all stored codes and fix any other transmission codes first. The Chrysler manual starts by checking for related codes.
- Check the transmission fluid level and condition using your owner's manual procedure (many need the engine running and the fluid warm). Low fluid is the simplest cause, per KBB.
- Look for transmission fluid leaks under the car and around the transmission pan and cooler lines. KBB says to fix a leak before refilling.
- Note whether the fluid looks dark, burnt or full of debris; KBB lists dirty or contaminated fluid as a cause.
- Inspect the wiring and connector at the transmission for damage, corrosion or loose pins.
- Clear the code and see if it returns. If it comes back, KBB says diagnosis can be very difficult, so a transmission shop is the next step.
Typical fixes
- Repair any leak and top up or correct the fluid level with the fluid your manufacturer specifies (KBB, RepairPal)
- Service the transmission fluid and filter if the fluid is dirty (KBB; RepairPal lists a fluid and filter change as a related repair)
- Repair damaged sensor or solenoid wiring and connectors (Chrysler service manual, RepairPal)
- Replace the line pressure sensor if it reads differently from a mechanical pressure gauge (Chrysler service manual)
- Replace a plugged filter, or repair the valve body, pressure regulator valve or oil pump if internal problems are found (Chrysler service manual)
- Replace and program the TCM or PCM only after the other checks pass (Chrysler service manual, RepairPal)
Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.
🛠 When to call a pro
- The transmission slips, won't shift, overheats or is in limp mode
- The fluid level is correct and the code keeps coming back
- Testing needs a mechanical pressure gauge and a scan tool that reads live line pressure, as the Chrysler manual specifies
- Debris in the pan or a plugged filter suggests internal wear
Where to buy
Plain search links. Always match parts to your exact year, make, model and engine.
FAQs
Is P0868 serious?
Yes. RepairPal rates it Urgent and KBB calls it extremely serious, since low fluid pressure affects shifting and can overheat or damage the transmission.
Can I drive with P0868?
Only gently and for short distances if it still shifts normally. KBB says not to drive long distances, and if the car is stuck in one gear, overheating or in limp mode, call a shop before driving it.
Can low transmission fluid cause P0868?
Yes. Low fluid level is listed as a cause by RepairPal, KBB and the Chrysler service manual. KBB notes a leak must be fixed before refilling.
How much does it cost to fix P0868?
None of the sources give a repair cost. It can range from adding fluid or fixing a leak to a sensor, wiring or internal transmission repair, so get a diagnosis or a written estimate first.
Sources
Last reviewed 2026-10-22. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.