P0847 on 2009-2014 Honda Fit: 3rd Clutch Pressure Switch Causes and Fixes

What's Unique About the 2009-2014 Honda Fit

The 5-speed automatic transmission (Model SP5A) in this generation of Honda Fit, like many other Honda models from the same era, is known for having these pressure switches fail. The failure is almost always the switch itself rather than a more serious internal transmission problem, a fact Honda has noted in diagnostic procedures. This makes the P0847 code on a Fit a very common, well-documented issue with a straightforward and inexpensive fix that many owners can perform themselves.

Symptoms You May Notice

• Flashing 'D' (Drive) indicator light on the instrument cluster.
🎬 See what a flashing D light looks like and how to fix it.
• Check Engine Light is on.
• Transmission will not shift properly or feels stuck in one gear (typically 3rd).
• Harsh or jerky shifting before entering limp mode.
• Inability to use Sport mode or paddle shifters, if equipped.

Most Likely Causes

1. Failed 3rd Clutch Transmission Fluid Pressure Switch 🔴 High Probability → Shop Transmission Assembly These pressure switches are a well-known, high-failure item across many Honda models of this era. Some reports suggest the original design allowed moisture intrusion through a vent, leading to premature failure.
   How to confirm: After confirming the wiring connector is clean and secure, replacing the switch is the most common and effective diagnostic step. A mechanic with a Honda-specific scan tool (HDS) could monitor the switch's on/off status during a drive to confirm it is not changing state correctly, but for a DIYer, replacement is often faster and cheaper than advanced diagnostics. 🎬 Watch this step-by-step diagnosis and repair of the P0847 code. A 'Circuit Low' code can be confirmed by checking for continuity to ground on the signal wire at the PCM connector with the switch disconnected.
   Typical fix: Replace the 3rd clutch pressure switch and its aluminum sealing washer. Clear the codes after replacement.
   Est. part cost: $25-$75
2. Wiring or Connector Issue ⚪ Low Probability
   How to confirm: Visually inspect the single-wire harness and connector leading to the pressure switch for any signs of damage, corrosion, or loose pins. A multimeter can be used to check for a short to ground on the signal wire with the switch disconnected. With the key on and connector unplugged, the wire should have approximately 5 volts.
   Typical fix: Repair the damaged section of wiring or clean/replace the connector.
   Est. part cost: $5-$20
3. Low or Dirty Transmission Fluid ⚪ Low Probability → Shop Transmission Assembly While unlikely to cause a 'Circuit Low' code, which is electrical, extremely low or degraded fluid can affect hydraulic operation and pressure.
   How to confirm: Check the transmission fluid level and condition using the dipstick. The fluid should be at the correct level and reddish/pink in color, not dark brown or black. A user on fitfreak.net noted that a fluid flush did not solve their P0847 code.
   Typical fix: Perform a transmission fluid drain and fill using Honda Genuine ATF-DW1. This is critical for overall transmission health but is unlikely to fix a P0847 code on its own.
   Est. part cost: $40-$80

Rare But Worth Checking

• Faulty Powertrain Control Module (PCM): This is extremely rare. Honda explicitly states this code is caused by an electrical circuit problem, not an internal mechanical issue. The switch and wiring must be exhaustively ruled out before considering the PCM as the cause. Diagnostic procedure suggests that if there is no continuity (short) in the wire between the PCM and the switch, the PCM may need to be replaced.

Diagnosis Steps

1. Read the trouble codes with an OBD-II scanner to confirm P0847 is present.
2. Check the transmission fluid level and condition. If low or very dirty, perform a drain and fill. This is good maintenance, though unlikely to be the root cause.
3. Locate the 3rd clutch pressure switch. On the 2009-2014 Fit, it is on the front of the transmission case, accessible from underneath the driver's side of the car, often near the dipstick tube. You may need to remove a portion of the plastic splash shield for better access.
4. Inspect the electrical connector and wiring going to the switch. Look for any obvious damage, corrosion, or loose connections. The connector has a tab you must press to release it.
5. If the wiring looks good, the most common and effective step is to replace the pressure switch.
6. Disconnect the electrical connector. Use a 22mm or 7/8" deep socket or wrench to unscrew the old switch. Be prepared for a small amount of transmission fluid (about 20ml) to drip out.
7. Ensure the old aluminum sealing washer is removed with the old switch.
8. Install the new switch with a new washer. Torque to specification (typically around 14 ft-lbs or 20 N·m). Do not overtighten.
9. Reconnect the electrical connector and reinstall the splash shield.
10. Clear the trouble codes with the scanner and perform a test drive to ensure the flashing 'D' light and Check Engine Light do not return.

Parts You'll Likely Need

• 3rd Clutch Transmission Fluid Pressure Switch (OEM #28600-RG5-004) — This is the component that fails and directly causes the P0847 code. The original part number may be 28600-RG5-003 or 28600-RG5-013, which has been superseded by the improved 28600-RG5-004.
  Trusted brands: Honda (Genuine), Standard Motor Products, Intermotor
  OEM price range: $50-$75
  Aftermarket price range: $25-$50
• Transmission Fluid Pressure Switch Sealing Washer/Gasket (OEM #90471-PW7-A00) — This aluminum washer is a one-time use crush washer and must be replaced with the switch to prevent leaks. It is often sold separately.
  Trusted brands: Honda (Genuine)
  OEM price range: $2-$5
  Aftermarket price range: $1-$3
• Honda ATF-DW1 Automatic Transmission Fluid (OEM #08200-9008) — Recommended for topping off any fluid lost during the switch replacement or for performing a drain and fill. Using genuine Honda fluid is highly recommended for their transmissions.
  Trusted brands: Honda (Genuine)
  OEM price range: $10-$15 per quart

Related Codes That Often Appear With This One

• P0756 — P0756 refers to 'Shift Solenoid B Performance or Stuck Off'. A pressure switch fault can sometimes confuse the computer's diagnostics for the shift solenoids, causing both codes to appear. Typically, fixing the P0847 pressure switch will also resolve the P0756 code. A manufacturer service news article titled "Hard or Delayed Shifting with A/T DTCs P0756 and P0847" further documents this relationship (NHTSA ODI #10836670).
• P0848 — This code is for 'Transmission Fluid Pressure Sensor/Switch 'B' Circuit High'. It relates to the same switch but indicates an open circuit instead of a short. It's less common but points to the same component or its wiring.

Platform-Specific Known Issues

• The 3rd gear pressure switch is a very common failure point on second-generation Fits, with many owners reporting the issue between 70,000 and 150,000 miles.
• A Reddit user with a 2010 Fit described the classic symptoms appearing every few thousand miles before finally replacing the switch. They noted the repair took less than 5 minutes once the car was on ramps.
• A user on the Unofficial Honda FIT Forums confirmed the fix is simple: 'Jack up, remove that section of plastic sheild, un hook connector, unscrew old one and washer rescrew in new one and new washer put connector on finished. The only thing it is indicative is that those sensors are total crap.'
• NHTSA ODI #11132314 describes a situation where a dealer found code P0847 for Transmission Fluid Pressure Switch B (3rd Clutch) indicating a "short or stuck on" condition while the vehicle was being driven on city streets.

Mechanic-Grade Diagnostic Values

• Voltage on the signal wire at the switch connector (connector unplugged, key ON) — expected: ~5.0 V. Failure: 0V would indicate a wiring issue from the PCM; significantly lower voltage could also indicate a problem.
• Continuity check of the signal wire — expected: No continuity to ground. Failure: Continuity to ground indicates a short circuit in the wiring harness between the PCM and the switch.

Scan Tool Commands That Help

• Honda Diagnostic System (HDS): Check 3rd Pressure Switch Status (ON/OFF) — This live data PID is used to monitor the switch's reported state. For a P0847, the HDS will likely show the switch as 'ON' even when it should be 'OFF' (e.g., when not in 3rd gear). This confirms the electrical fault seen by the PCM.
• Honda Diagnostic System (HDS): Clear DTCs — Used after replacing the faulty component to clear the P0847 code from the PCM's memory and extinguish the Check Engine Light and flashing 'D' light.

Wiring & Ground Locations

• PCM Connector B (51P), Pin 25 — The PCM is located in the engine bay. Connector B is one of the main connectors to the module.. This is the specific pin for the 3rd clutch pressure switch signal wire (OP3SW wire). A technician would test for a short to ground at this pin with the connector disconnected to isolate a wiring fault from a switch fault.
• G101 — Typically located on the engine block or thermostat housing, serving as a primary engine and PCM ground point.. While a bad ground here would likely cause multiple, more severe issues than just P0847, ensuring G101 is clean and tight is a fundamental step in diagnosing any engine or transmission electrical problem. A poor ground can cause floating voltages and erratic sensor behavior.

Real Owner Repair Stories

• Unofficial Honda FIT Forums user 'Subie' (2007 Honda Fit Sport AT (GD3, first generation, but same issue and part logic applies)) — CEL on and flashing 'D' light. Code P0847. Car stuck in 3rd gear, paddle shifters not working.
  ❌ Tried (didn't work) Clearing the code (it returned intermittently), Topping off low transmission fluid (blinking D light went off, but CEL with P0847 remained)
  ✅ What actually fixed it Replacing the 3rd clutch pressure switch (referred to as 'sw B (bottom item #9)' in the parts diagram) resolved all symptoms. The CEL went away after the fix.
• NHTSA ODI #10836670 — An owner reported the check engine light coming on and the vehicle shifting roughly while in motion on city streets. Diagnostics revealed codes P0756 and P0847, leading to repairs based on Honda service documentation regarding hard or delayed shifting.

OEM Part Supersession History

• 28600-RG5-003, 28600-RG5-013 → 28600-RG5-004 — The original switch design reportedly had a vent hole that could allow moisture to enter, leading to internal corrosion and premature failure. The updated -004 part is believed to have an improved design to prevent this.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• Lost Motion Spring Failure 🔴 High — Common enough to trigger a recall (11-010) for some 2009-2010 VINs. Can cause engine noise or, in rare cases, stalling. (Ref: Recall 11-010)
• Loose Spark Plugs 🟠 Medium — Plugs can loosen over time, potentially causing misfire codes (P030x) and damage to the coil pack. Usually detected between 60,000 and 100,000 miles. (Ref: TSB ATS160714)
• Water Leaks into Cabin 🟡 Low — Leaks can occur from poorly sealed body seams in the rear wheel well or front cowl area, leading to wet carpets. A product update was issued for the rear wheel well leak (A11-013). (Ref: Product Update A11-013)
• VTC Actuator Rattle on Cold Start 🟡 Low — A brief, loud rattle for 1-2 seconds on a cold start is common. While startling, it is generally considered harmless by many owners, though a TSB exists for later models. (Ref: TSB 16-088 (for 2015-16 models, but describes the same issue))
• Sticking Rear Hatch Handle 🟡 Low — The exterior handle for the rear liftgate can get stuck or fail to operate smoothly.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: For this specific repair, buying a used pressure switch is strongly discouraged. The part is a known high-failure item with a low cost for a new, improved OEM part.

What to inspect on the donor part:

• Not applicable as a used part is not recommended.

OEM-only on this vehicle (don't cheap out):

• While quality aftermarket switches exist (e.g., Standard Motor Products), the price difference compared to the genuine Honda part is often small. Given the critical function and the improved design of the OEM part (28600-RG5-004), using the genuine part is the safest choice to avoid repeat failures.

Aftermarket brands forum-validated for this vehicle:

• Standard Motor Products (Intermotor)
• NTK

Brands owners have reported issues with on this vehicle:

• Unbranded, no-name parts from online marketplaces should be avoided, as their quality and durability are unknown and they are a frequent cause of repeat failures.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0848 — This code is for 'Transmission Fluid Pressure Switch 'B' Circuit High'. It points to the opposite electrical fault in the exact same circuit as P0847. The cause is often the same failed switch or a different wiring problem (e.g., an open circuit instead of a short to ground).
• P0842 — This code indicates 'Circuit Low' for pressure switch 'A'. Since the context states that 'these pressure switches are a well-known, high-failure item across many Honda models of this era', a failure of one switch (causing P0847) suggests others may be prone to failure as well.
• P0843 — The 'Circuit High' counterpart to P0842 for pressure switch 'A'. It relates to P0847 because it points to a failure of a similar component in the same transmission, which is known to have issues with its pressure switches.
• P030X — Misfire codes (P0301, P0302, etc.) are related as they point to another common, known issue on the 2009-2014 Fit: loose spark plugs. While mechanically unrelated to the transmission, it's another frequent fault an owner might encounter.
• U0101 — Lost Communication With TCM (Transmission Control Module). In a severe case where a wiring harness is damaged, not only could the pressure switch circuit be shorted (causing P0847), but overall communication with the transmission's computer could be lost, triggering this code.

Frequently Asked Questions