P0846 on Ram vehicles
Trans Fluid Pressure Sensor B Range / Performance — what it means on a Ram, whether it's safe to drive, and the fixes by model and year.
P0846 on a Ram means trans fluid pressure sensor b range / performance. Most vehicles stay drivable short-term, but diagnose it promptly. The most common cause is failed transmission fluid pressure sensor / switch "b". Pick your Ram model below for its known failure patterns, recalls, and TSBs.
What does P0846 mean on a Ram?
P0846 is set when the transmission controller reads the "B" transmission fluid pressure sensor or switch and the value it reports does not make sense for the hydraulic state the transmission is supposed to be in. Either the pressure is outside the expected range, or it fails to change when a shift or a clutch application should have changed it. Two very different things produce that: a faulty sensor, or a correctly-working sensor honestly reporting a real hydraulic pressure problem. Which one you have decides whether this is a modest repair or a transmission rebuild, so the diagnosis matters more here than the part.
P0846 is a standardized OBD-II code, so its definition is the same on every Ram. What differs by model and engine is which cause is most likely — pick your Ram model below for a diagnosis tuned to its known failure patterns, recalls, and TSBs.
Is it safe to drive a Ram with P0846?
In most cases a Ram stays drivable for short trips with P0846 active, but diagnose and repair it promptly. This is a high-severity code — ignoring it can lead to further damage or a failed emissions test. Exact tolerance depends on the model and engine.
What causes P0846 on a Ram?
| Cause | Likelihood | Estimated repair (USD) |
|---|---|---|
| Failed transmission fluid pressure sensor / switch "B" — We have not published a verified cost range for this specific part, and part pricing varies widely between transmissions — ask your shop for the part number and a written quote rather than trusting a generic figure. | Most common | — |
| Damaged wiring or fluid-contaminated external transmission connector | Common | $100–$500 |
| Low transmission fluid level or contaminated fluid | Common | $100–$400 |
| Contaminated fluid causing valve sticking in the valve body | Common | $150–$500 |
| Worn or stuck valve body losing pressure regulation | Occasional | $600–$2,000 |
| Internal transmission damage or a worn pump producing genuinely low pressure | Occasional | $2,500–$6,500 |
| Failed TCM driver or input for the pressure sensor circuit | Rare | $500–$1,500 |
Repair costs are typical US ranges and vary by Ram model, model year, and labor rate. A diagnostic trouble code is a symptom, not a guaranteed failed part — confirm the root cause before replacing anything.
P0846 by Ram model
Select your Ram model and year for a P0846 diagnosis tuned to that vehicle's failure patterns, recalls, and TSBs.
Ram 1500
1,537 NHTSA owner complaints · 35 recalls on record across the years covered below.
Complaint and recall counts are NHTSA totals for the model years covered on this site, not counts specific to P0846.
P0846 on other makes
Other codes on Ram vehicles
P0846 on a Ram: frequently asked questions
What does diagnostic trouble code P0846 mean on a Ram?
P0846 is set when the transmission controller reads the "B" transmission fluid pressure sensor or switch and the value it reports does not make sense for the hydraulic state the transmission is supposed to be in. Either the pressure is outside the expected range, or it fails to change when a shift or a clutch application should have changed it. Two very different things produce that: a faulty sensor, or a correctly-working sensor honestly reporting a real hydraulic pressure problem. Which one you have decides whether this is a modest repair or a transmission rebuild, so the diagnosis matters more here than the part. P0846 is a standardized OBD-II code, so the definition is the same on every Ram — which cause is most likely varies by model and engine.
What are the symptoms of P0846 on a Ram?
Check Engine Light is illuminated. Harsh, delayed, or erratic shifts. Transmission slipping or flaring between gears. Transmission enters limp / failsafe mode, often locked in one gear. Reduced fuel economy. Often paired with P0700 from the transmission controller
What causes P0846 on a Ram?
Failed transmission fluid pressure sensor / switch "B" (most-common). Damaged wiring or fluid-contaminated external transmission connector (common). Low transmission fluid level or contaminated fluid (common). Contaminated fluid causing valve sticking in the valve body (common). Worn or stuck valve body losing pressure regulation (occasional). Internal transmission damage or a worn pump producing genuinely low pressure (occasional). Failed TCM driver or input for the pressure sensor circuit (rare)
Is it safe to drive a Ram with P0846?
In most cases a Ram stays drivable for short trips with P0846 active, but it should be diagnosed and repaired promptly — this is a high-severity code. Ignoring it can lead to further damage or a failed emissions test. Exact tolerance depends on the model and engine.