P0700 on 2003-2007 Honda Accord: Transmission Control System Malfunction Guide

What's Unique About the 2003-2007 Honda Accord

The 7th generation Accord's 5-speed automatic transmission (coded as BAYA or MAYA for V6 models, and BCLA/MCLA for 4-cylinder models) is known to be susceptible to issues with pressure switches and solenoids. While P0700 is a generic code, on this specific vehicle, it frequently points toward these components. Owners often experience harsh shifting, especially between 2nd and 3rd gear, or a flashing 'D' (Drive) indicator light along with the Check Engine Light. These transmissions, particularly in the early 2003-2004 V6 models, had a high failure rate, sometimes before 100,000 miles. Ignoring these symptoms can lead to more significant internal transmission damage, a known weak point for this era of Honda automatics.

Symptoms You May Notice

• Check Engine Light is on
• Flashing 'D' or 'D4' indicator light on the dashboard
• Harsh or delayed gear shifts, particularly when cold
• Abrupt or jerky downshifts when coming to a stop
• Vehicle hesitates or feels like it's in neutral when trying to accelerate
• Transmission getting stuck in one gear ('limp mode')
• Reduced fuel economy
• Loud noise from the transmission during shifts.

Most Likely Causes

1. Faulty Transmission Pressure Switch (3rd or 4th Clutch) 🔴 High Probability → Shop Transmission Assembly These switches are a very common failure point on this generation of Honda automatic transmissions, leading to erratic shift behavior. They are responsible for telling the TCM if the hydraulic pressure for a gear change was successful.
   How to confirm: Use a capable scanner to check for specific codes like P0780 (Shift Malfunction) or other codes pointing to pressure switch circuits. The switches can be tested for continuity with a multimeter. For the V6, the 3rd clutch switch is located on the front of the transmission, near the radiator. The 2nd and 4th gear switches are often located under the battery tray.
   Typical fix: Replace the faulty pressure switch. It is highly recommended to use genuine Honda parts for these sensors. The 3rd gear switch is often part number 28610-RAY-003 (which supersedes to 28610-RKE-004) and the 2nd/4th gear switch is often 28600-P7Z-003.
   Est. part cost: $40-$80
2. Failed Shift Solenoid or Torque Converter Clutch (TCC) Solenoid 🔴 High Probability → Shop Automatic Transmission Torque Converter Solenoids control the flow of fluid to engage gears. They can become clogged with metallic debris from normal wear or fail electrically over time, causing a variety of shifting problems.
   How to confirm: Scan for specific solenoid-related codes (e.g., P0740 for TCC, P0753 for Shift Solenoid A). Solenoids can be tested for resistance with a multimeter (often around 12-25 Ohms is expected for shift solenoids). Clogged solenoid screens are a very common issue and can sometimes be cleaned as a temporary or permanent fix.
   Typical fix: Replace the specific failed solenoid pack or clean the screens. They are typically mounted externally on the transmission case, making them accessible after removing the battery and air filter housing.
   Est. part cost: $100-$300
3. Low or Degraded Transmission Fluid 🟡 Medium Probability → Shop Transmission Assembly Incorrect fluid level or fluid that has broken down can cause overheating, poor hydraulic pressure, and shifting problems. Honda transmissions are notoriously sensitive to fluid type and condition.
   How to confirm: Check the transmission fluid level and condition with the engine OFF and the vehicle on level ground. The fluid should be red and clear, not dark brown, black, or smell burnt.
   Typical fix: Perform a transmission fluid drain-and-fill (typically 3-4 quarts) using only Honda Genuine ATF-DW1. ATF-DW1 is the backward-compatible replacement for the original ATF-Z1 fluid and offers better performance. Multiple drain-and-fills are often recommended over a pressurized flush on high-mileage transmissions.
   Est. part cost: $40-$100

Rare But Worth Checking

• Faulty Transmission Control Module (TCM) or Powertrain Control Module (PCM): → Shop Engine Control Module (ECM) While less common, a failing computer can cause a P0700 code with various shifting symptoms. In some cases, both the solenoid and the PCM needed to be replaced to fix the issue. This is usually suspected when P0700 appears alone with no other codes, and all wiring/sensors test good.
• Internal Transmission Failure: → Shop Transmission Assembly If the fluid contains significant metal shavings (more than a fine paste on the magnetic drain plug), it points to mechanical wear of clutches or gears. This was a significant issue on 2003-2004 V6 models, often involving the 3rd gear clutch pack. This is the worst-case scenario and would require a transmission rebuild or replacement.
• Damaged wiring harness or connectors: The wiring to the external solenoids and pressure switches can become damaged or corroded, leading to intermittent signals and fault codes. A visual inspection of the harness is a key diagnostic step.
• Engine Performance Issues: A manufacturer service bulletin, Bulletin #A25-044, notes that a rich air/fuel mixture that fouls spark plugs can cause the PCM to misread sensor resistance, potentially triggering P0700 alongside misfire codes like P0300.

Diagnosis Steps

1. Check and verify the transmission fluid level and condition. Ensure the vehicle is on level ground and the engine is off. The fluid should be between the marks on the dipstick and should be reddish, not brown/black or burnt-smelling.
2. Use an OBD-II scanner capable of reading Honda-specific transmission codes to retrieve the codes from the TCM. The P0700 code is just a general alert; the secondary codes (e.g., P0740, P0780) are what you need for diagnosis.
3. Research the specific codes found. A P0780 or pressure switch code points towards solenoids and switches. A P0740 points to the TCC solenoid. Follow the specific diagnostic tree for that code.
4. Inspect the wiring and connectors to the transmission solenoids and pressure switches for any visible damage, corrosion, or loose connections. These are located on the exterior of the transmission case.
5. If a specific solenoid is implicated, test its resistance with a multimeter against factory specifications (often around 12-25 ohms for many Honda solenoids). If a pressure switch is implicated, test it for continuity.
6. If solenoids are suspected, consider removing them to inspect and clean the small mesh screens underneath. These frequently get clogged with debris and cleaning them can resolve the issue.
7. If no specific codes are found besides P0700, the fluid is good, and wiring appears intact, the issue could be an intermittent electrical problem or a failing Transmission Control Module (TCM).

Parts You'll Likely Need

• Transmission Pressure Switch (3rd Clutch) (OEM #28610-RAY-003 / 28610-RKE-004) — This switch is a very common failure item on 7th generation Accords, directly causing harsh shifting (especially 2-3 shift) and setting codes that trigger P0700.
  Trusted brands: Genuine Honda
  OEM price range: $50-$90
  Aftermarket price range: $25-$50
• Transmission Pressure Switch (2nd/4th Clutch) (OEM #28600-P7Z-003) — Along with the 3rd clutch switch, this is another high-failure item that causes shift quality issues and related trouble codes.
  Trusted brands: Genuine Honda
  OEM price range: $50-$90
  Aftermarket price range: $25-$50
• Shift Solenoid Assembly (OEM #28250-P7W-003 (Varies by specific solenoid)) — Shift solenoids are another primary cause of shifting issues that lead to a P0700 code. They can fail electrically or become clogged with debris.
  Trusted brands: Genuine Honda, Rostra
  OEM price range: $150-$350
  Aftermarket price range: $80-$200

Related Codes That Often Appear With This One

• P0730 — Indicates an incorrect gear ratio, often triggered by a slipping clutch or a faulty pressure switch. NHTSA ODI #11713610 describes an instance where P0730 and P0700 were identified during a diagnostic test for transmission failure.
• P0740 — Points to a fault in the Torque Converter Clutch (TCC) solenoid circuit. NHTSA ODI #10479205 describes a situation where the Check Engine, VSA, and TCS lights came on simultaneously with codes P0700 and P0740.
• P0780 — Indicates a shift malfunction, often related to a faulty shift solenoid or pressure switch. It's a general indicator of a problem with a specific shift event (e.g., the 2-3 shift).
• P1751 — A Honda-specific code indicating a mechanical fault in the hydraulic system, often linked to a failed solenoid or clogged solenoid filter.
• P0716 — Input/Turbine Speed Sensor Circuit Range/Performance. NHTSA ODI #11451395 reports permanent transmission codes P0716 and P0700 where a dealership could not initially pinpoint the issue.
• P0705 — Transmission Range Sensor Circuit Malfunction. NHTSA ODI #11174984 notes a vehicle where P0700, P0705, and P0740 were all present shortly after purchase.

Technical Service Bulletins (TSBs) & Recalls

• While no specific TSB is for P0700 directly, TSB 02-027 for the related Acura TL (1999-2003) addresses symptoms like a flashing D5 light, harsh shifting, and ATF leaks, which are highly relevant to the Accord's issues.
• Manufacturer Bulletin #A25-044 notes that P0700 can sometimes be stored alongside engine-related codes like P0172 or P219C due to air/fuel mixture issues fouling spark plugs.

Platform-Specific Known Issues

• { "title": "Owner Experience: P0700 and P0780 Fixed by Replacing Pressure Switches", "description": "An owner on a forum reported a flashing D4 light, P0700, and P0780 codes. The car would shift harshly from 2nd to 3rd gear. The problem was resolved by replacing both the 3rd and 4th gear pressure switches. The owner emphasized using OEM Honda parts as aftermarket switches failed quickly." }
• { "title": "DIY Repair: Cleaning Solenoid Screens for P0740", "description": "A popular YouTube video with over a million views demonstrates cleaning the clutch pressure control solenoid screens on a related Acura TL. The user had a P0740 code and severe shifting problems. Cleaning the metallic sludge off the tiny filter screens restored normal transmission function completely, saving thousands on a potential rebuild." }

Mechanic-Grade Diagnostic Values

• Shift Solenoid A, B, or C Resistance — expected: 12 - 25 Ohms. Failure: A reading outside this range, or an open circuit (OL), indicates a failed solenoid.
• A/T Clutch Pressure Control Solenoid Valve Resistance — expected: 3 - 10 Ohms. Failure: Resistance outside this range indicates a faulty solenoid valve.
• PCM/TCM Main Ground (G101) to Chassis Resistance — expected: Less than 1.0 Ohm. Failure: A higher resistance reading indicates a poor ground connection, which can cause erratic electronic behavior and false codes.

Hidden / Shadow Codes Worth Checking

• Transmission-Specific DTCs (e.g., P0741, P0847, P1751): → Shop Transmission Assembly P0700 is a generic request from the TCM to the ECM to turn on the check engine light. The actual, specific fault code is stored within the Transmission Control Module (TCM) itself and is necessary for diagnosis. (see via A scan tool that can communicate directly with the Honda Transmission Control Module (TCM), such as the dealer-level Honda i-HDS or an advanced professional scanner (e.g., some Snap-on, Autel models).)

Scan Tool Commands That Help

• Honda Diagnostic System (HDS): SHIFT SOL TEST (in MISCELLANEOUS TEST MENU) — This bidirectional test allows a technician to command a specific shift solenoid (e.g., Shift Solenoid A) to actuate. The technician listens for an audible click from the solenoid. If no click is heard, it confirms a mechanical or electrical failure of that specific solenoid, pinpointing the faulty component.
• Honda Diagnostic System (HDS) or equivalent: Read AT Data List (e.g., 3rd Pressure Switch status) — When diagnosing a pressure switch code (like P0847 or P0848), a technician can view the live on/off status of the switch as reported to the TCM. This helps determine if the switch is stuck on, stuck off, or if the fault is in the wiring/PCM, by comparing the live data to the actual circuit conditions.

Wiring & Ground Locations

• G101 — For V6 (J30) engines, on the left side of the engine near the intake manifold. For 4-cylinder (K24) engines, it's a ring terminal with multiple wires bolted to the thermostat housing or intake manifold plenum on the driver's side.. This is the main power and logic ground for the Powertrain Control Module (PCM), which houses the TCM functions. A poor connection at G101 due to corrosion or looseness can cause a host of intermittent electrical problems, including false transmission codes like P0700, by providing unstable voltage to the control unit.
• Shift Solenoid B vs. C Connector — On the external valve body of the transmission.. To prevent misdiagnosis and incorrect part replacement, it's critical to know that the connector for shift solenoid valve B is black, and the connector for shift solenoid valve C is brown. Swapping them during reinstallation will cause immediate shifting problems and codes.
• Transmission Wiring Harness — Runs from the PCM/TCM to the various sensors and solenoids on the transmission case.. The harness can be susceptible to damage from heat, road debris, or rodent activity. A chafed or broken wire can cause an open or short in a solenoid or sensor circuit, directly triggering a fault code in the TCM and illuminating P0700.

Real Owner Repair Stories

• Honda-Tech forum member (2001 Honda Accord (Similar transmission architecture and components)) — Check Engine Light with transmission codes.
  ✅ What actually fixed it The user tested the clutch pressure control solenoids and found they had correct resistance (3-10 Ohms) and clicked when power was applied. After cleaning the solenoids and connectors of any oil or dirt, the problem was resolved. This highlights that sometimes the issue is a poor connection or minor contamination rather than a failed part.
• NHTSA ODI #11174984 — An owner reported that after purchasing a used vehicle with 136,000 miles, the check engine light appeared within a week. A transmission shop confirmed codes P0700, P0705, and P0740 were present, all relating to the automatic transmission.
• NHTSA ODI #10479205 — An owner experienced the Check Engine, VSA, and TCS lights coming on. A repair shop identified codes P0700 (Automatic Transmission Fault) and P0740 (Torque Converter Clutch Malfunction).

OEM Part Supersession History

• 28610-RAY-003, 28610-RAY-013 → 28610-RKE-004 — Part consolidation and potential design revision by Honda.
  Heads up: The new part number 28610-RKE-004 is the correct, current replacement for the 3rd clutch pressure switch. It also supersedes several other pressure switch part numbers, including 28600-P7Z-003, making it a common replacement for multiple switch locations on various Honda models.

Model Year Variations Within This Range

• 2003-2004 V6: These early 7th generation V6 models were particularly known for premature automatic transmission failures, often related to the 2nd or 3rd gear clutch packs. NHTSA complaints for powertrain issues are significantly higher for these years compared to 2005-2007.
• 2006-2007 V6: The 5-speed automatic transmissions in the 2006-2007 V6 models carry a 'BAYA' code. These are considered by enthusiasts and mechanics to be more robust and reliable than the transmissions in the earlier 2003-2005 models. While still susceptible to solenoid and switch failures, the risk of catastrophic internal failure is lower.
• 2003-2007: The 5-speed automatic transmission used in V6 models is a different unit from the 5-speed automatic used in 4-cylinder models. While they share similar failure points (solenoids, switches), part numbers and specific locations may differ.

Diagnostic Flowchart

Other Known Issues on This Vehicle

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

• Automatic Transmission Failure (V6 Models) 🔴 High → Shop Transmission Assembly — Very common, especially on 2003-2004 models. Can occur under 100,000 miles. Less frequent on later years but still a major concern.
• Stereo Backlight / Radio Display Failure 🟡 Low — Extremely common across all years. The circuit board for the radio display backlight fails, making it unreadable at night.
• Excessive Oil Consumption (4-Cylinder K24 Engine) 🟠 Medium — Common at higher mileage (over 100,000 miles). Can be caused by sticking piston rings.
• Power Steering Hose Leak / Whine 🟡 Low — A whine during turning is common, often caused by air entering the system via a failing O-ring on the power steering pump inlet. A leaking high-pressure hose is also common.
• Cracked Exhaust Manifold (4-Cylinder) 🟠 Medium — The catalytic converter is integrated into the exhaust manifold, which is prone to cracking over time, causing an exhaust leak and potentially a P0420 code.
• Failing Starter Motor 🟠 Medium — A common failure item at higher mileage, resulting in a no-crank, no-start condition.
• Clear Coat / Paint Failure 🟡 Low — Widespread issue, particularly on dark-colored cars. The clear coat peels and flakes off, leading to a poor appearance and potential for rust.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A complete, low-mileage used transmission assembly from a 2006-2007 V6 donor car (BAYA code) can be a smart choice if your 2003-2005 transmission has suffered catastrophic internal failure. Used external components like solenoid assemblies can also be cost-effective, provided they are from a low-mileage, non-failed transmission.

Donor-vehicle mileage cap: roughly under 120000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• For a full transmission: Ask for a video of the donor car running and driving, if possible. Check the color and smell of the transmission fluid from the donor; it should be reddish, not black or burnt-smelling.
• For solenoids/sensors: Inspect electrical connectors for cracks, corrosion, or broken tabs. Check that the mesh filter screens on solenoids are intact and not clogged with excessive metal debris.
• Verify the transmission code (e.g., 'BAYA' for the updated V6 unit) stamped on the casing to ensure you're getting the desired version.

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

• Transmission Pressure Switches (3rd and 4th clutch)
• Transmission Fluid (Honda ATF-DW1)

Aftermarket brands forum-validated for this vehicle:

• Rostra (for solenoids)
• Standard Motor Products (SMP) (for solenoids)

Brands owners have reported issues with on this vehicle:

• Unbranded, 'no-name' pressure switches and solenoids from online marketplaces are a significant gamble and often fail prematurely.

Real Owner Stories

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

Related OBD-II Codes

• P0780 — Shift Malfunction — often appears with P0700 when transmission pressure switches (3rd or 4th clutch) fail to signal successful gear changes.
• P0740 — Torque Converter Clutch (TCC) Solenoid circuit malfunction — a common secondary code that identifies the specific solenoid causing the P0700 alert.
• P0753 — Shift Solenoid A Electrical — indicates an electrical failure in the solenoid pack, which triggers the TCM to set the P0700 general fault code.

Frequently Asked Questions