P242A — Exhaust Gas Temperature Sensor Circuit Bank 1 Sensor 3

powertrain (engine/transmission)

Is it safe to drive?

Short-term driving is OK 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.

How to diagnose with an OBD scanner

  1. Read the code and freeze frame Connect an OBD2 scanner, confirm P242A is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
  2. Check for companion codes and TSBs 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. Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the exhaust gas temperature sensor circuit bank 1 sensor 3 for damage, corrosion, chafing or poor contact.
  4. Subsystem check Measure reference voltage, ground and signal continuity at the component connector.
  5. Subsystem check Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
  6. Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P242A does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for P242A (parts and labor, USD, independent shop rates): Repair wiring or connectors: $80–$250; Replace the faulty sensor or actuator: $150–$500; Control module repair: $300–$1,000. Overall, fixing P242A 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.

Common questions

How do I diagnose P242A myself?

Start with a scan: confirm P242A, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the sensor and actuator circuits, and verify the suspect component against live data before buying parts.

What are the symptoms of P242A?

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

Will P242A clear itself?

Sometimes P242A 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 P242A mean?

Exhaust Gas Temperature Sensor Circuit Bank 1 Sensor 3 (P242A): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by open or shorted wiring in the circuit, poor ground connection, blown fuse feeding the circuit.

How much does it cost to fix P242A?

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

What does P242A mean?

When P242A appears on a scan, it means the control module has flagged a problem in the sensor and actuator circuits: exhaust gas temperature sensor circuit bank 1 sensor 3. The fault sits in the powertrain (engine/transmission) group of the OBD2 standard.

In this definition, “Bank 1” is the side of the engine that contains cylinder 1 and “Sensor 3” is the downstream (after the catalytic converter) sensor. Mixing up banks and sensor positions is the most common DIY mistake with this code — verify the physical location before replacing anything.

The module monitors this system continuously while driving. When readings fall outside the expected range for a defined number of drive cycles, it stores P242A and switches on the warning light. Freeze frame data saved with the code shows the exact conditions — rpm, load, temperature, speed — at the moment the fault was detected, which is the best starting point for diagnosis.

Common symptoms of P242A

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

What causes P242A?

  • blown fuse feeding the circuit
  • faulty sensor or actuator of the affected circuit
  • poor ground connection
  • open or shorted wiring in the circuit
  • corroded, loose or damaged connector
  • control module driver fault

How to diagnose P242A

  1. Connect an OBD2 scanner, confirm P242A 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 exhaust gas temperature sensor circuit bank 1 sensor 3 for damage, corrosion, chafing or poor contact.
  4. Measure reference voltage, ground and signal continuity at the component connector.
  5. Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
  6. Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P242A does not return.

How to fix P242A

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

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

How much does it cost to fix P242A?

Repair cost depends on which component actually failed. Typical scenarios for P242A (parts and labor, USD, independent shop rates):

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

Overall, fixing P242A 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 P242A?

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