P2046 — Reductant Temperature Sensor Circuit Intermittent

What does OBD2 code P2046 mean?

P2046 — Reductant Temperature Sensor Circuit Intermittent. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: faulty sensor or actuator of the affected circuit, corroded, loose or damaged connector, blown fuse feeding the circuit.

How do I diagnose P2046 myself?

Start with a scan: confirm P2046, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the reductant temperature sensor, and verify the suspect component against live data before buying parts.

What is the most common cause of P2046?

The most common causes are: faulty sensor or actuator of the affected circuit, corroded, loose or damaged connector, blown fuse feeding the circuit.

Will P2046 clear itself?

Sometimes P2046 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.

How much does it cost to fix P2046?

Replace the faulty sensor or actuator — $150–$500; Control module repair — $300–$1,000; 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 P2046 mean?

The engine control module sets P2046 when it detects a fault in the sensor and actuator circuits. In practical terms: reductant temperature sensor circuit intermittent. The code belongs to the powertrain (engine/transmission) group of OBD2 codes.

“Intermittent” means the fault on the reductant temperature sensor circuit comes and goes — the module sees correct values part of the time. These faults are almost always mechanical: a loose pin, a half-broken wire or a connector that loses contact with vibration or temperature changes.

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 P2046 — engine load, rpm, temperature, speed — tells you exactly when the problem occurs, so reproduce those conditions when testing.

Common symptoms of P2046

• 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 P2046?

• loose or backed-out connector pin
• contact affected by vibration or heat
• wire broken inside intact insulation
• corroded, loose or damaged connector
• open or shorted wiring in the circuit
• control module driver fault
• faulty sensor or actuator of the affected circuit
• blown fuse feeding the circuit

How to diagnose P2046

1. Connect an OBD2 scanner, confirm P2046 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 temperature sensor for damage, corrosion, chafing or poor contact.
4. Reproduce the fault: wiggle the harness and tap the reductant temperature sensor while watching the live signal; heat and vibration usually make intermittent faults appear.
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 P2046 does not return.

How to fix P2046

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

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

How much does it cost to fix P2046?

Repair cost depends on which component actually failed. Typical scenarios for P2046 (parts and labor, USD, independent shop rates):

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

Overall, fixing P2046 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 P2046?

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