P2652 on 2017 Honda Odyssey: Rocker Arm Oil Pressure Switch 'B' (Bank 1) Stuck On

What's Unique About the 2017-2017 Honda ODYSSEY

The 2017 Odyssey uses the J35Z8 V6 engine, which features Honda's VCM system to save fuel by shutting down cylinders under light load. This system relies heavily on oil pressure, which is monitored by several switches. The P2652 code is specific to the switch on Bank 1 🎬 Watch: Fixing P2652 limp mode on a newer Odyssey (the rear bank, near the firewall) that controls part of this system. Failure of these switches is a well-documented issue across many Honda and Acura models using the J-series V6 engine, as evidenced by multiple technical service bulletins.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Check Engine Light (Malfunction Indicator Light) is on
• Rough engine operation or rough idle
• Reduced engine performance or vehicle entering 'limp mode'
• Poor acceleration
• Decreased fuel economy
• Flashing 'D' (Drive) indicator on the instrument cluster
• Audible tapping or ticking from the engine

Most Likely Causes

1. Failed Rocker Arm Oil Pressure Switch (Bank 1) 🔴 High Probability This is a very common failure point on Honda's J-series V6 engines due to the switch's internal components wearing out and getting stuck. It is the most cited fix in owner forums and repair videos.
   How to confirm: After confirming oil level is correct, this is the most likely culprit. The diagnostic procedure involves disconnecting the switch's electrical connector with the engine off. Use a multimeter to check for continuity between the terminal on the switch and a good engine ground. If continuity exists, the switch is internally shorted ('stuck on') and must be replaced.
   Typical fix: Replace the rocker arm oil pressure switch on Bank 1 (rear cylinder head). This requires a 24mm deep socket and ratchet. Be sure to also replace the O-ring (part # 91319-PAA-A01) that seals the switch.
   Est. part cost: $45-$65
2. Low or Dirty Engine Oil 🟡 Medium Probability The VCM/VTEC system is hydraulic and highly sensitive to oil level, viscosity, and condition. Low or contaminated oil can cause pressure reading errors or clog small passages.
   How to confirm: Check the engine oil dipstick on a level surface. The level should be between the marks, and the oil should not be excessively dark, gritty, or past its service interval.
   Typical fix: Perform an oil and filter change using the correct viscosity oil (0W-20). Clear the code and see if it returns.
   Est. part cost: $40-$80
3. Wiring or Connector Issue ⚪ Low Probability
   How to confirm: Visually inspect the single wire (often green) and connector going to the Bank 1 oil pressure switch for any signs of damage, corrosion, or looseness. An open circuit in the wire can also cause a high voltage reading, mimicking a stuck switch.
   Typical fix: Repair the damaged wire or clean/replace the connector.
   Est. part cost: $5-$50

Rare But Worth Checking

• Clogged VCM Oil Passages or Faulty Solenoid: If replacing the switch doesn't solve the issue, the problem could be a blockage in the oil passages within the VTEC solenoid assembly (spool valve) or a faulty solenoid itself. This is less common but worth investigating before suspecting the ECM.
• Faulty Powertrain Control Module (PCM): This is extremely rare. The PCM should only be considered after all other possibilities, including wiring, switches, and mechanical components, have been thoroughly checked and ruled out.

Diagnosis Steps

1. Verify the engine oil level and condition. Top off or change the oil if necessary. This is the first and simplest check.
2. Scan for other codes. If P3400 is present, it strongly reinforces the diagnosis of a Bank 1 VCM component failure.
3. Locate the Rocker Arm Oil Pressure Switch 'B' on Bank 1. This is on the rear cylinder head, closer to the firewall. It will have a single-wire connector, often green.
4. Inspect the electrical connector and wire for any damage, corrosion, or looseness.
5. Disconnect the connector. With the engine off, use a multimeter set to continuity (ohms). Place one probe on the metal terminal inside the switch and the other probe on a good ground (like the engine block).
6. If the multimeter beeps or shows very low resistance (continuity), the switch is stuck in the 'on' position and must be replaced. This is the most common failure mode.
7. If continuity does not exist, the problem may be an open or short in the wiring harness between the switch and the PCM.
8. If the switch and wiring are confirmed to be good, the issue may be mechanical, such as low oil pressure to the head or a faulty rocker arm oil control solenoid, which requires more advanced diagnostics.

Parts You'll Likely Need

• Rocker Arm Oil Pressure Switch (Bank 1) (OEM #37240-R70-A04) — This is the most frequent cause for code P2652 on this engine. It is a direct replacement part that resolves the 'stuck on' signal. This part number supersedes older versions like 37240-R70-A03 and 37240-R70-A02.
  Trusted brands: Genuine Honda, NTK/NGK, Standard Motor Products (SMP)
  OEM price range: $45-$65
  Aftermarket price range: $25-$50
• Oil Pressure Switch O-Ring (OEM #91319-PAA-A01) — This O-ring provides the seal for the pressure switch. It is recommended to replace it whenever the switch is removed to prevent oil leaks. It is often sold separately.
  Trusted brands: Genuine Honda
  OEM price range: $2-$5
  Aftermarket price range: $1-$3

Related Codes That Often Appear With This One

• P3400 — P3400 (Valve Pause System [VPS] Stuck Off Bank 1) is often stored with P2652. A Honda Technical Service Bulletin explicitly links these two codes, indicating they stem from the same root cause related to the Bank 1 VCM system.
• U0401 — Invalid Data Received from ECM/PCM. This code can appear in the transmission control module (TCM) as a secondary fault because the engine is not running correctly, causing communication issues between modules.

Technical Service Bulletins (TSBs) & Recalls

• ATI&01192022901: Request for information on vehicles with MIL on and DTC P2652 (Rocker Arm Oil Pressure Switch B [Bank 1] Stuck On) & P3400 (Valve Pause System [VPS] Stuck Off Bank 1) stored. Affects 2017 Odyssey, Pilot, and Ridgeline.

Platform-Specific Known Issues

• Honda issued a Technical Service Bulletin (TSB), #ATI&01192022901, requesting information on 2017 Odysseys, Pilots, and Ridgelines that present with both P2652 and P3400 codes, along with a rough running complaint. This indicates it's a known issue Honda was actively investigating for this specific model year and its platform mates.

Mechanic-Grade Diagnostic Values

• Rocker Arm Oil Pressure Switch 'B' Signal Wire Voltage (Engine Running) — expected: ~0V. Failure: Voltage remains high, near battery voltage (e.g., 12V+), indicating the switch is not closing to ground under pressure.
• Rocker Arm Oil Pressure Switch 'B' Signal Wire Voltage (Key On, Engine Off) — expected: System Voltage (~12V). Failure: Voltage is 0V, which could indicate a short to ground in the wiring harness.
• VCM System Oil Pressure (at switch port) — expected: 45 kPa (6.5 psi) or more. Failure: Pressure below this threshold suggests a mechanical issue, such as a clogged oil passage or faulty spool valve, rather than a bad switch.
• Freeze Frame Data: ROCKER ARM OIL PRESSURE (Cold Start) — expected: 92 psi or less. Failure: Pressure greater than 92 psi can indicate a sticking oil pump relief valve, a rare issue documented in TSB 13-055.

Scan Tool Commands That Help

• Honda Diagnostic System (HDS): VTEC+VCM TEST, then select CDVEB TEST — This is a dealer-level functional test used to verify if the rocker arm oil pressure switch 'B' is operating correctly without having to perform manual electrical checks. It can help confirm an intermittent failure.

Wiring & Ground Locations

• PCM Connector C (51P), Pin 34 — This is one of the main connectors at the Powertrain Control Module (PCM), which on many Hondas is located in the engine bay near the battery or in the passenger footwell area.. This specific pin carries the signal from the Bank 1 'B' oil pressure switch. A diagnostic step for a suspected wiring short involves checking for continuity between this pin and body ground.
• G201 / G301 — Main engine compartment ground points, typically located on the frame rails at the left front of the engine compartment.. While the switch grounds through the engine block, the PCM and its related circuits rely on clean chassis grounds like these. A poor main ground can cause floating voltages and erratic sensor readings across the system.

Real Owner Repair Stories

• Reddit user on r/MechanicAdvice (2016 Honda Pilot EX-L (FWD, 3.5L V6)) — Engine started driving rough, Check Engine Light with code P2652.
  ❌ Tried (didn't work) The user first sought advice before trying any fixes.
  ✅ What actually fixed it The owner replaced the rocker arm oil pressure switch. They reported, 'Cleared the codes and everything sounds and feels normal again.'
• AcuraZine user 'thoiboi' (2017 Acura RDX Tech (J35 Engine Family)) — Vehicle suddenly went into limp mode with a flashing check engine light and would not accelerate. Also experienced a judder/shudder.
  ✅ What actually fixed it The dealership diagnosed code P2652 (Rocker Arm oil pressure switch B stuck ON) and replaced the faulty oil pressure switch, which resolved the limp mode and performance issues.

OEM Part Supersession History

• 37240-R70-A01, 37240-R70-A02, 37240-R70-A03 → 37240-R70-A04 — Part has been updated by the manufacturer over time to improve reliability.
  Heads up: Using unverified aftermarket switches is not recommended, as some have a poor reputation for reliability with electrical sensors. Also, do not use PTFE (Teflon) tape on the threads; the new switch relies on its O-ring for sealing, and tape fragments can break off and clog critical oil passages.