P0871: How to Diagnose & Fix — Transmission Fluid Pressure Sensor/Switch "C" Circuit Range/Performance
4 vehicles · 4 makes · $150-$3,500 repair
How to diagnose and fix P0871: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Dodge Dart · 2013–2016
The 2.4L Dart paired with the Aisin 6-speed automatic experiences TCM failures that cause erratic shifting, failure to shift, and limp mode. The TCM mounted on the transmission is exposed to heat and vibration, leading to internal circuit board failures. Unlike the DDCT issues on 1.4T models, this affects the conventional automatic transmission.
Common Symptoms
- Transmission stuck in limp mode (2nd gear only)
- Erratic or harsh shifting
- Check engine light with transmission codes
- Transmission fails to shift into higher gears
- Delayed engagement when shifting from Park
How to Fix
Replace the TCM (Mopar 68164473AH or equivalent). The replacement TCM must be programmed with the VIN and transmission adaptation data at the dealer using wiTECH. Aftermarket remanufactured TCMs are available but must still be dealer-programmed. Cost is $600-$1,200 installed.
Sources for this issue (1)
RAM 1500 · 2013–2024
The 8-speed (ZF 8HP70 / TorqueFlite) develops a torque-converter clutch shudder felt as a vibration/judder around 30-50 mph light throttle, along with harsh downshifts, drive-engagement slam, and occasional limp mode (stuck in one gear with CEL). Root causes are degraded/aged transmission fluid and worn torque-converter clutch material, sometimes with valve-body or solenoid issues. Ram markets the trans as 'sealed/lifetime fill,' but ZF recommends fluid service every ~40-60k miles, and skipping it drives most of these complaints.
Common Symptoms
- Shudder/vibration at light throttle 30-50 mph
- Harsh or clunky downshifts
- Slam into drive/reverse
- Limp mode (stuck gear) with CEL
- Delayed or flaring shifts
How to Fix
Start with a proper fluid-and-filter service using the correct ZF 8HP fluid (many shudders clear up with fresh fluid) and apply the latest transmission software/TCM updates. If shudder persists, inspect/replace the torque converter; harsh-shift or limp events may require valve-body or solenoid repair. Adopt a 40-60k-mile fluid interval rather than the 'lifetime' claim to prevent recurrence.
Sources for this issue (2)
Jeep Wrangler · 2012–2025
Wranglers equipped with the ZF-based 8-speed automatic (845RE/850RE/8HP) are widely reported to shift harshly or jerk, especially the 1-2 shift and when accelerating from a stop, plus delayed engagement when moving from Park to Drive or Reverse. Many cases are resolved by a Transmission Control Module (TCM) software/calibration reflash, while others stem from low or degraded transmission fluid, a failing valve body, or a worn shift solenoid. NHTSA and J.D. Power survey data show higher-than-class-average shifting complaint rates. Unexpected downshifts that flare engine RPM and overheating during towing/off-road are also documented.
Common Symptoms
- Harsh or jerky 1-2 shift
- Clunk from Park to Drive/Reverse
- Delayed engagement
- Unexpected downshifts / RPM flare
- Hesitation during acceleration
- Transmission overheat warning when towing
How to Fix
Start with the latest TCM/PCM calibration flash from the dealer (many harsh-shift complaints are a software fix). Verify transmission fluid level and condition using the correct fill procedure and ZF-spec fluid; perform a fluid/filter service if dark or burnt. If shifting faults persist, diagnose the valve body and shift solenoids; relearn shift adaptives after any service. Severe internal failures require valve body or transmission replacement.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Mopar 68218925AB ZF 8 & 9 Speed automatic-transmission fluid, one quartOEMMopar 68218925AB
Confirm the exact transmission service specification and quantity; not a universal-ATF substitute and not a standalone cure for software or intern
- Genuine Mopar 68362041AC Wrangler transmission oil panOEMMopar 68362041AC
Select by VIN and transmission code; the page's broad engi
- Genuine Mopar 68417054AB transmission-oil filterOEMMopar 68417054AB
Separate filter branch for a VIN-confirmed non-PHEV JL eight-speed pan-drop service Fitment/availability: Shown with the 68362041AC metal-pan family in Mopar diagrams. Confirm transmission, engine and VIN; do not apply automatically to t…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (2)
Chevrolet Silverado 2500HD · 2001–2019
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P0871 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0871 mean?
P0871 stands for "Transmission Fluid Pressure Sensor/Switch "C" Circuit Range/Performance." This code sets when the transmission control module receives a signal from transmission fluid pressure sensor/switch C that is out of the expected range or implausible for the current conditions. This sensor monitors hydraulic pressure inside the transmission, which the module relies on to control clutch apply and shift quality. Symptoms can include harsh, delayed, or erratic shifts, slipping, or the transmission entering a failsafe mode. The cause is typically the sensor, actual fluid pressure problems, or the wiring.
What are the most common causes of P0871?
The most common causes of P0871 are: Faulty transmission fluid pressure sensor/switch C, Low or degraded transmission fluid, Internal hydraulic leak or low line pressure, Stuck or faulty pressure control solenoid, Wiring or connector issues, Valve body wear or contamination, Faulty transmission control module (less common). The specific cause varies by vehicle.
How much does it cost to fix P0871?
Repair costs for P0871 range from $150 to $3,500, depending on the vehicle and root cause.
Which vehicles are affected by P0871?
Au7o has documented P0871 across 4 vehicle models from 4 manufacturers: Chevrolet, Dodge, Jeep, RAM.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.