P2064 — Reductant/Regeneration Supply Control Circuit High

What are the symptoms of P2064?

Drivers most often notice: possible limp mode depending on the affected component, the affected system operates intermittently or not at all, Check Engine Light on, increased fuel consumption in some cases.

Will P2064 clear itself?

Sometimes P2064 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.

What does OBD2 code P2064 mean?

OBD2 code P2064 flags a problem with the sensor and actuator circuits (reductant/regeneration supply control circuit high). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit.

How do I diagnose P2064 myself?

Start with a scan: confirm P2064, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the reductant/regeneration supply control, and verify the suspect component against live data before buying parts.

How much does it cost to fix P2064?

Control module repair — $300–$1,000; Replace the faulty sensor or actuator — $150–$500; Repair wiring or connectors — $80–$250. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.

What does P2064 mean?

When P2064 appears on a scan, it means the control module has flagged a problem in the sensor and actuator circuits: reductant/regeneration supply control circuit high. The fault sits in the powertrain (engine/transmission) group of the OBD2 standard.

“Circuit high” means the control module sees a voltage on the reductant/regeneration supply control circuit that is above the expected range — typically close to battery voltage. Physically this points to a short to a power feed, a broken ground return, or a failed component pulling the signal line high.

This code does not appear from a single bad reading: the module must see the fault condition repeat under defined operating conditions before it turns on the warning light. The freeze frame captured with P2064 — engine load, rpm, temperature, speed — tells you exactly when the problem occurs, so reproduce those conditions when testing.

Common symptoms of P2064

• possible limp mode depending on the affected component
• the affected system operates intermittently or not at all
• Check Engine Light on
• increased fuel consumption in some cases

What causes P2064?

• failed reductant/regeneration supply control pulling the signal high
• signal wire shorted to battery positive
• open ground return of the reductant/regeneration supply control
• corroded, loose or damaged connector
• control module driver fault
• poor ground connection
• blown fuse feeding the circuit
• faulty sensor or actuator of the affected circuit
• open or shorted wiring in the circuit

How to diagnose P2064

1. Connect an OBD2 scanner, confirm P2064 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
2. Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
3. Visually inspect the wiring harness and connectors related to the reductant/regeneration supply control for damage, corrosion, chafing or poor contact.
4. With the reductant/regeneration supply control disconnected, measure signal voltage at the harness connector: a high reading with the component unplugged indicates a short to power in the harness; if it drops to normal, the component itself is faulty.
5. Measure reference voltage, ground and signal continuity at the component connector.
6. Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
7. Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P2064 does not return.

How to fix P2064

Start with the cheapest and most common causes before replacing expensive parts:

• Control module repair — $300–$1,000
• Replace the faulty sensor or actuator — $150–$500
• Repair wiring or connectors — $80–$250

How much does it cost to fix P2064?

Repair cost depends on which component actually failed. Typical scenarios for P2064 (parts and labor, USD, independent shop rates):

• Control module repair: $300–$1,000
• Replace the faulty sensor or actuator: $150–$500
• Repair wiring or connectors: $80–$250

Overall, fixing P2064 usually costs between $80 and $1,000. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Can you drive with P2064?

In most cases the car remains drivable, possibly with reduced performance or a disabled auxiliary system. If symptoms include stalling, no-start or brake/steering warnings, treat it as urgent.

Related OBD2 codes

• P2000: NOx Adsorber Efficiency Below Threshold Bank 1
• P2001: NOx Adsorber Efficiency Below Threshold Bank 2
• P2002: Diesel Particulate Filter Efficiency Below Threshold Bank 1
• P2003: Diesel Particulate Filter Efficiency Below Threshold Bank 2
• P2004: Intake Manifold Runner Control Stuck Open Bank 1
• P2005: Intake Manifold Runner Control Stuck Open Bank 2