P0846 on 2013-2018 Ram 1500: Transmission Pressure Switch Causes and Fixes

What's Unique About the 2013-2018 Ram 1500

The 2013-2018 Ram 1500 is unique because it was offered with two different primary automatic transmissions: the Chrysler-built 6-speed 65RFE and the ZF-sourced 8-speed 8HP70. This trouble code, P0846, is a well-documented and common issue specifically related to the 6-speed 65RFE, where the pressure switches are integrated into a single solenoid pack. Conversely, there is very little evidence to suggest that P0846 is a common fault code for the 8-speed 8HP70 transmission; issues on that transmission often present with different codes related to the mechatronic unit or specific clutch packs.

Symptoms You May Notice

• Check Engine Light is on
• Transmission is stuck in one gear (limp mode, often 3rd or 4th gear)
• Harsh or erratic shifting
• Delayed gear engagement
• Inability to shift into Reverse
• Vehicle may feel like it has a loss of power during acceleration

Most Likely Causes

1. Failed Transmission Solenoid Pack (Solenoid/TRS Assembly) 🔴 High Probability On the 65RFE transmission, the pressure switches are not serviced individually but are integrated into the solenoid pack. This entire assembly is a known failure point due to heat, age, and flexing of the internal circuit board, causing internal electrical faults. It is the most common cause for P0846.
   How to confirm: After verifying fluid level and condition, and checking for wiring issues, a diagnostic scan tool can monitor the state of the 2C pressure switch. If the switch's reported state (open/closed) is irrational for the current gear, the solenoid pack is the likely culprit. A continuity test of the circuit from the PCM connector can also reveal an open circuit within the pack. A bent pin in the main transmission connector can also cause this issue, as documented in one repair video.
   Typical fix: Replace the entire transmission solenoid pack, which is located on the valve body inside the transmission. This involves draining the fluid, dropping the pan, and removing the valve body to access the pack.
   Est. part cost: $250-$450
2. Low or Contaminated Transmission Fluid 🟡 Medium Probability
   How to confirm: Check the transmission fluid level using the dipstick with the engine running and the transmission warm. Note the fluid's color and smell; it should be bright red and not smell burnt. Dark, burnt, or glittery fluid indicates a more severe internal problem, such as clutch debris, which can clog passages and affect pressure.
   Typical fix: Perform a transmission fluid and filter change using Mopar ATF+4. If the fluid level was low, identify and repair the source of the leak. A fluid change alone will not fix a faulty solenoid pack.
   Est. part cost: $75-$150
3. Damaged Wiring or Connectors ⚪ Low Probability The main transmission harness connector is exposed to road debris and heat from the exhaust, which can lead to damage over time. A bent pin from a previous repair is also a possible, though rare, cause.
   How to confirm: Visually inspect the wiring harness leading to the main transmission connector for any signs of chafing, melting, or corrosion. Disconnect the connector and check for bent, pushed-out, or corroded pins. Perform a continuity test on the 2C pressure switch sense circuit between the TCM/PCM and the transmission connector.
   Typical fix: Repair the damaged section of the wiring harness, straighten or replace the faulty connector pin, or replace the connector itself.
   Est. part cost: $20-$100

Rare But Worth Checking

• Internal Hydraulic Leak: A leak in the 2C clutch hydraulic circuit inside the transmission can cause a loss of pressure that the sensor correctly reports. This is less common than a sensor failure and requires an air pressure test of the circuit to confirm. This could also be caused by a damaged check ball in the valve body.
• Faulty Powertrain Control Module (PCM): It is possible for the PCM itself to fail, but this is extremely rare. All other possibilities, especially the solenoid pack and wiring, should be exhaustively ruled out before considering PCM replacement.

Diagnosis Steps

1. Check the transmission fluid level and condition. If low, top it off and check for leaks. If dirty or burnt, a fluid and filter change is a good first step, but the underlying cause must still be found.
2. Use a diagnostic scan tool to confirm P0846 is the primary code and check for any other related transmission codes, such as P0700 or P0845. Note the freeze-frame data to see when the fault occurred.
3. Visually inspect the main transmission electrical connector and the associated wiring harness for any obvious damage, corrosion, or loose connections. Carefully check for bent or pushed-out pins inside the connector.
4. If possible, use an advanced scan tool to monitor the live data for the '2C Pressure Switch'. Observe its state (Open/Closed) while shifting gears (or as commanded by the tool). An illogical reading points towards the solenoid pack.
5. If wiring is suspected, perform a continuity test on the 2C pressure switch sense circuit (typically a Dark Green/Yellow wire) from the PCM connector to the transmission connector.
6. If the fluid, wiring, and external checks are good, the most likely cause is the internal solenoid pack. Proceed with dropping the transmission pan to replace it.

Parts You'll Likely Need

• Transmission Solenoid Pack (65RFE) (OEM #68376695AB (supersedes 52120000AA, 68376695AA)) — This is the most common failure for code P0846 on the 6-speed transmission, as it contains the pressure switches that fail and trigger the code.
  Trusted brands: Mopar, Dorman (609-040), Sonnax (44836B-RRP - Remanufactured), Standard Motor Products (TCS309)
  OEM price range: $400-$500
  Aftermarket price range: $250-$400
• Transmission Filter Kit (65RFE) (OEM #5013470AC (Kit)) — The two filters (spin-on cooler return filter and sump filter) and the pan gasket must be replaced whenever the transmission pan is removed for service. The OEM pan gasket is reusable if in good condition, but aftermarket kits often include a new one.
  Trusted brands: Mopar, Wix, ATP
  OEM price range: $60-$90
  Aftermarket price range: $30-$50
• Mopar ATF+4 Automatic Transmission Fluid (OEM #68218057AC (Quart), 68218058AC (Gallon)) — This is the required fluid type for the 65RFE transmission. Using the correct fluid is critical for transmission health. A pan drop and solenoid replacement will require approximately 6-8 quarts.
  Trusted brands: Mopar, Valvoline, Castrol (licensed ATF+4)
  OEM price range: $12-$18 per quart
  Aftermarket price range: $8-$12 per quart

Related Codes That Often Appear With This One

• P0700 — This is a generic code indicating the Transmission Control Module (TCM) has stored a fault. It acts as a 'master light' to turn on the Check Engine Light and is almost always present with specific transmission codes like P0846.
• P0845 — This code, '2C Hydraulic Pressure Test Failure', often appears alongside P0846. It indicates a failure in the same hydraulic circuit, further pointing towards an issue with the 2C clutch pressure reading, often originating from the same solenoid pack failure.

Platform-Specific Known Issues

• source — A user with an '05 Durango (which uses a related RFE transmission) experienced P0846 and P0845. After confirming fluid was good, they replaced the solenoid pack, which resolved the issue. This demonstrates the commonality of the fix across the RFE transmission family.
• source — A mechanic diagnosing a 2011 Ram 1500 with P0846 performed extensive electrical testing pointing to a bad solenoid pack. Before dropping the pan, a final inspection of the main connector revealed a bent pin for the 2C pressure switch circuit was the true cause.

Mechanic-Grade Diagnostic Values

• 2C Pressure Switch Internal Resistor — expected: ~300 Ohms. Failure: An infinite/open reading indicates a failed resistor inside the solenoid pack.
• (T147) 2C Pressure Switch Sense Circuit Voltage — expected: Approx. 5V with Key On, Engine Off (switch open). Near 0V when the 2C hydraulic circuit is pressurized (switch closed).. Failure: Voltage stuck low (near 0V) when it should be high, or stuck high when it should be low, indicates a circuit fault or failed switch. An absence of voltage is interpreted by the controller as a closed switch.
• (T147) 2C Pressure Switch Sense Circuit Resistance to Ground — expected: Infinite resistance (Open circuit). Failure: Resistance below 5.0 Ohms indicates a short to ground in the wiring harness.
• Solenoid Pack Mounting Bolt Torque — expected: 50 in-lbs (5.6 Nm). Failure: N/A
• Valve Body to Transmission Case Bolt Torque — expected: 105 in-lbs (12 Nm). Failure: N/A

Scan Tool Commands That Help

• wiTECH or equivalent professional scan tool: Quick Learn Procedure — This procedure is mandatory after replacing the solenoid pack or valve body. It allows the TCM to relearn clutch fill volumes and pressure characteristics, which is critical for preventing harsh shifting and future codes after the repair.
• wiTECH or equivalent professional scan tool: Pressure Switch Test — Using a transmission simulator tool in conjunction with the scan tool, a technician can manually toggle pressure switch states to verify the PCM is receiving the signals correctly, isolating a wiring problem from an internal transmission problem.

Wiring & Ground Locations

• 2C Pressure Switch Sense Circuit — Wire runs from Pin 14 on the main transmission solenoid connector to Pin 2 of the PCM C4 connector.. This is the specific wire (typically Dark Green with a Yellow stripe) that carries the signal for the 2C pressure switch. All electrical tests for opens, shorts to ground, or shorts to voltage are performed on this wire.
• Main Transmission Connector — Large, round, gray connector located on the driver's side of the 65RFE transmission case.. This is the primary connection point between the vehicle's main harness and the internal transmission electronics, including the solenoid pack. It is a common location for bent pins, corrosion, or damage.
• Engine/Chassis Ground Strap — There is a critical ground strap from the firewall/body to the back of the cylinder head on the driver's side.. A loose or corroded main ground can cause erratic behavior in multiple electronic systems, including the PCM/TCM. This can lead to incorrect sensor readings and seemingly random transmission fault codes.

Real Owner Repair Stories

• YouTube channel 'Phillip Bailey' (2011 Ram 1500 with 5.7L Hemi and 6-speed auto) — Check engine light with code P0846 and limp mode stuck in 4th gear. The problem occurred immediately after an engine replacement.
  ❌ Tried (didn't work) Extensive electrical testing showed an open circuit on the 2C pressure switch signal wire, pointing towards a failed solenoid pack.
  ✅ What actually fixed it Before replacing the solenoid pack, a final inspection with a mirror revealed a bent pin (Pin 15 in this model year, which corresponds to the 2C circuit) inside the main transmission connector. Straightening the pin resolved the issue completely.
• Reddit user in r/mechanic (2012 Ram 1500) — P0750 code (Shift Solenoid 'A') and limp mode.
  ❌ Tried (didn't work) Replaced the solenoid pack, but the truck would not move in Drive or Reverse afterward., Replaced the solenoid pack again, but the P0750 code returned after a short time.
  ✅ What actually fixed it The issue was that the fault codes and transmission adaptive values were not properly reset with a bidirectional scan tool after the repair. The TCM was still operating based on the old fault data and had to be forced to relearn the new component with a 'Quick Learn' procedure.

OEM Part Supersession History

• 52120000AA, 68376695AA → 68376695AB — Updated design to improve reliability and address common failure modes.
  Heads up: The 65RFE uses a gray connector solenoid pack. Earlier 45RFE/545RFE transmissions used a white or black connector pack. While some sources claim a white connector pack can be used in a 65RFE, it is highly recommended to use the correct gray connector Mopar part (68376695AB) to ensure compatibility.