P2488 – EGT Sensor Circuit High (Bank 2 Sensor 2)

System: Powertrain | Standard: ISO/SAE Controlled | Fault type: Circuit High | Location: Bank 2, Sensor 2

Definition source: SAE J2012/J2012DA (industry standard)

DTC P2488 indicates the engine control system has detected an abnormally high electrical signal in the exhaust gas temperature (EGT) sensor circuit for Bank 2 Sensor 2. This is an electrical “circuit high” condition, meaning the module is seeing a higher-than-expected input rather than confirming a temperature problem by itself. The exact sensor location and how the module interprets the signal can vary by vehicle, so always verify sensor placement, wiring routing, and diagnostic procedures using the correct service information before testing or replacing parts.

What Does P2488 Mean?

P2488 – EGT Sensor Circuit High (Bank 2 Sensor 2) means the powertrain control module has detected a high-input condition on the exhaust gas temperature sensor circuit identified as Bank 2 Sensor 2. Under SAE J2012 DTC conventions, “circuit high” points to an electrical issue such as a short to voltage, an open in a ground/return path, a disconnected connector, a wiring fault, or a sensor internal fault that drives the signal high. The code itself does not confirm an exhaust over-temperature event; it reports an out-of-range electrical signal state.

Quick Reference

  • System: Powertrain
  • Official meaning: EGT Sensor Circuit High (Bank 2 Sensor 2)
  • Standard: ISO/SAE controlled
  • Fault type: Circuit High
  • Severity: MIL illumination is possible and the vehicle may enter torque reduction or reduced-power strategies depending on how EGT data is used.

Symptoms

  • MIL: Check engine light illuminated, possibly after a short drive or under load.
  • Reduced power: Torque limiting or limp mode may occur if EGT input is required for protection strategies.
  • Regeneration changes: Aftertreatment control events may be inhibited, delayed, or behave unusually (varies by vehicle).
  • Poor drivability: Hesitation, limited acceleration, or inconsistent response may be noticed during load changes.
  • Additional DTCs: Related exhaust temperature, aftertreatment, or sensor supply/reference codes may store alongside P2488.
  • Failed readiness: Emissions monitors may not complete due to EGT input being considered invalid.

Common Causes

  • Sensor 2 (Bank 2) EGT sensor signal circuit shorted to power (B+), causing a high input
  • Open circuit in the EGT sensor signal or return circuit (varies by vehicle), allowing the input to be pulled high
  • High resistance in the EGT sensor ground/return path (corrosion, damaged wire, loose terminal) raising the effective signal
  • Connector problems at the EGT sensor or harness junction (water intrusion, spread pins, poor pin fit, backed-out terminals)
  • Damaged harness near hot exhaust components (melted insulation, chafing to a powered circuit, pinched wiring)
  • Incorrect or contaminated electrical connection after recent service (misrouted harness, incomplete connector latch, wrong connector mated)
  • EGT sensor internal electrical fault that drives or biases the circuit high
  • Control module input circuit issue (rare) after power/ground integrity and wiring have been verified

Diagnosis Steps

Tools: a scan tool with live data and freeze-frame access, a digital multimeter, and basic back-probing or terminal test adapters. A wiring diagram and connector pinout from service information are essential because EGT sensor circuits and reference/return strategies vary by vehicle. Use safe lifting/support equipment and heat protection when working near exhaust components.

  1. Confirm P2488 is present and record freeze-frame data and all stored/pending codes. Note operating conditions (load, temperature, speed) and whether any related exhaust/temperature or power supply DTCs are also set.
  2. Identify the correct component location for Bank 2 Sensor 2 using service information. Visually verify you are inspecting the intended EGT sensor and connector, since bank/sensor numbering varies by vehicle.
  3. Perform a thorough visual inspection with the engine off and cooled as needed: inspect the sensor body, lead, connector, and harness routing near the exhaust. Look for melted insulation, chafing, contact with sharp edges, or signs of water intrusion/corrosion at the connector.
  4. Check connector integrity: ensure the connector is fully seated and locked; inspect terminals for spread pins, poor pin fit, pushed-back terminals, or contamination. Repair terminal issues per service procedures and recheck.
  5. Use the scan tool to view EGT-related live data (the affected sensor and any other EGT sensors if available). Compare the suspect sensor reading to the other bank/sensor readings at similar operating conditions. Log data while lightly changing engine speed/load; a circuit-high fault often shows an implausibly high, fixed, or non-responsive value.
  6. Perform a wiggle test while monitoring live data and/or the PID state: gently manipulate the harness at the sensor connector, along the routing near hot components, and at any intermediate connectors. If the reading spikes high or the fault status toggles, isolate the section that reacts and inspect for intermittent opens or short-to-power.
  7. Key off, disconnect the EGT sensor connector and inspect for evidence of heat damage at the pins. With the sensor disconnected, check for an unexpected voltage present on the harness-side signal circuit (short-to-power indication). Consult service information to identify which pin is signal and which is return/ground.
  8. Check for an open or high resistance in the return/ground path: perform a voltage-drop test on the ground/return circuit under load where applicable (varies by vehicle and circuit design). Excessive drop indicates poor ground/return integrity, corrosion, or damaged wiring.
  9. Check continuity and isolation: measure continuity of the signal and return circuits end-to-end (sensor connector to control module or intermediate connector as defined in service info). Also check for short-to-power by verifying the signal circuit is not electrically connected to known power feeds.
  10. If wiring and connector checks pass, evaluate the sensor: follow service information for any specified sensor resistance or circuit checks (without relying on generic “normal values”). Replace the sensor only if test results indicate it is electrically faulty or biased high.
  11. After repairs, clear codes and perform a verification drive cycle while logging live data for the affected EGT sensor. Confirm the reading responds normally and that P2488 does not return as pending or confirmed.

Professional tip: If the fault is intermittent, focus on heat- and vibration-related harness issues near the exhaust. Secure the harness away from hot surfaces, restore protective loom/heat shielding as required, and re-run the wiggle test while monitoring live data to confirm the circuit no longer shows high-input behavior.

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Factory repair manual access for P2488

Check repair manual access

Possible Fixes & Repair Costs

Repair costs for P2488 vary widely because the same “circuit high” condition can be caused by wiring, connector, power/ground issues, the EGT sensor itself, or rarely a control module. Total cost depends on diagnostic time, parts replaced, and labor access.

  • Repair damaged wiring (chafed insulation, pinched harness, heat damage) in the EGT sensor (Bank 2 Sensor 2) signal and return circuits, then secure routing away from hot or sharp surfaces
  • Clean, tighten, or replace affected connector components (corroded terminals, loose pin fit, water intrusion), and apply appropriate terminal protection where specified by service information
  • Restore proper circuit integrity by correcting an open ground/return, missing shield/ground (if equipped), or poor splice that can drive the signal high
  • Correct a short-to-power condition in the signal circuit (or shared reference circuit, varies by vehicle) that forces an abnormally high input to the control module
  • Replace the EGT sensor (Bank 2 Sensor 2) only after verifying power, ground/return, and signal wiring are correct and the fault follows the sensor or fails component-level testing
  • Repair upstream power/ground distribution faults that affect sensor circuits (fuse/relay feed, ground point integrity), when confirmed by voltage-drop testing
  • Reflash or replace the control module only after all circuit checks pass and service information supports module-level diagnostics for a persistent high-input reading

Can I Still Drive With P2488?

You may be able to drive short distances, but do so cautiously and verify whether the vehicle has reduced-power operation, warning indicators, or abnormal exhaust/engine behavior. Because P2488 is an EGT sensor circuit high condition (Bank 2 Sensor 2), the control module may alter fueling, aftertreatment, or protection strategies, which can affect drivability. If you notice reduced power, harsh running, unusual heat-related warnings, or any safety-critical symptoms (stalling, no-start, brake/steering warnings), do not continue driving; diagnose and repair first.

What Happens If You Ignore P2488?

If ignored, the persistent high-input signal can cause the control module to make incorrect exhaust temperature decisions, potentially triggering repeated MIL illumination, reduced-power strategies, and inhibited or altered aftertreatment operation (varies by vehicle). Prolonged operation with inaccurate EGT feedback may contribute to poor performance, increased emissions, and possible thermal protection actions that reduce drivability until the electrical fault is corrected.

Compare nearby egt trouble codes with similar definitions, fault patterns, and diagnostic paths.

  • P2462 – EGT Sensor Circuit High (Bank 1 Sensor 3)
  • P2460 – EGT Sensor Circuit (Bank 1 Sensor 3)
  • P2489 – EGT Sensor Circuit Intermittent (Bank 2 Sensor 2)
  • P2487 – EGT Sensor Circuit Low (Bank 2 Sensor 2)
  • P2486 – EGT Sensor Circuit Range/Performance (Bank 2 Sensor 2)
  • P2461 – EGT Sensor Circuit Low (Bank 1 Sensor 3)

Key Takeaways

  • P2488 indicates an electrical “circuit high” condition in the EGT sensor circuit for Bank 2 Sensor 2, not a confirmed exhaust temperature problem by itself.
  • Most root causes are circuit-related: short-to-power, open ground/return, connector corrosion, terminal fit issues, or harness damage from heat and vibration.
  • Accurate diagnosis should prioritize wiring and connector testing, including voltage-drop checks and a wiggle test, before replacing parts.
  • Driving may be possible, but the vehicle can enter protection or reduced-power behavior depending on how it uses EGT input.
  • Fix only what testing proves; replacing the sensor without verifying circuit integrity can lead to repeat faults.

Vehicles Commonly Affected by P2488

  • Vehicles equipped with an exhaust gas temperature (EGT) sensor located downstream on Bank 2 (Bank 2 Sensor 2 location varies by vehicle)
  • Powertrains that use EGT feedback for aftertreatment management and thermal protection strategies
  • Applications with hot-zone harness routing near exhaust components where insulation can become brittle or damaged over time
  • Vehicles operated in high-heat or high-load duty cycles that increase underbody and exhaust-area temperatures
  • Platforms with underbody exposure to water, salt, or debris that can accelerate connector corrosion
  • Vehicles with recent exhaust, engine, or transmission service where harnesses/connectors may have been disturbed or misrouted
  • High-mileage vehicles where terminal tension, ground points, and splices may degrade
  • Vehicles that frequently experience vibration or flexing near the exhaust and sensor harness supports

FAQ

Does P2488 mean the exhaust gas temperature is too high?

No. P2488 specifically indicates an EGT sensor circuit high condition (Bank 2 Sensor 2). That means the control module is detecting an abnormally high electrical input on the circuit, which can be caused by wiring, connectors, or the sensor, and does not by itself confirm the actual exhaust temperature.

What is “Bank 2 Sensor 2” for an EGT sensor?

“Bank 2” refers to the engine side that is not Bank 1, and “Sensor 2” indicates a downstream EGT sensor position on that bank. The exact physical location varies by vehicle; consult service information and component location diagrams to identify the correct sensor.

What electrical problems commonly cause a “circuit high” fault on an EGT sensor?

Common electrical causes include a short-to-power on the signal circuit, an open or high-resistance ground/return path that biases the signal high, connector corrosion or water intrusion, damaged insulation near hot exhaust components, and terminal fit problems that create unstable or incorrect readings.

Should I replace the EGT sensor right away?

Not until basic circuit checks are completed. Because P2488 is a circuit high fault, verifying harness integrity, connector condition, and power/ground/return paths is the priority. Replace the sensor only after testing indicates it is the source of the high-input condition or the fault follows the sensor.

Will clearing the code fix P2488?

Clearing the code may turn off the MIL temporarily, but it will not correct the underlying circuit high condition. If the fault is still present, P2488 will typically reset after the required monitoring runs. A verified repair should be followed by clearing codes and confirming the fix with a complete drive cycle or service-information-directed test routine.

For a lasting repair, focus on proving the cause of the high-input signal with wiring and connector tests first, then confirm the fix by clearing codes and verifying the EGT sensor (Bank 2 Sensor 2) signal remains stable during a monitored road test.