P2390 – Turbocharger Boost Sensor Control High

System: Powertrain | Standard: ISO/SAE Controlled | Fault type: General

Definition source: SAE J2012/J2012DA (industry standard)

DTC P2390 indicates the powertrain control module has detected a “high” electrical condition related to the turbocharger boost sensor control circuit. In practice, this points to the sensor control signal being higher than expected for the operating conditions, often due to an electrical issue such as a short to power, an open ground, or wiring/connector faults—rather than confirming a mechanical turbocharger problem by itself. DTC behavior, enabling conditions, and the exact sensor/circuit routing vary by vehicle, so confirm component locations, pinouts, and test specifications using the correct service information.

What Does P2390 Mean?

P2390 means Turbocharger Boost Sensor Control High. Based on the official definition, the controller has determined the turbocharger boost sensor control circuit is reporting a high input/command condition outside what it expects. SAE J2012 defines the standardized structure and naming used for diagnostic trouble codes, while the vehicle’s control module logic determines when the fault is set. Because “control high” is an electrical/signal-high type fault, diagnosis should prioritize circuit integrity (power, ground, reference, signal routing, and connector condition) before considering component replacement.

Quick Reference

• System: Powertrain
• Official meaning: Turbocharger Boost Sensor Control High
• Standard: ISO/SAE controlled
• Fault type: Circuit High
• Severity: MIL illumination is possible and the vehicle may enter reduced-power operation, affecting drivability during acceleration or under load.

Symptoms

• MIL/Check Engine light: Warning lamp illuminated, possibly with pending and confirmed fault records.
• Reduced power: Limited acceleration or torque management during boost demand.
• Hesitation: Delayed or uneven response when throttle is applied, especially under load.
• Boost control irregularity: Perceived over- or under-assist behavior depending on how the system defaults when the signal is implausibly high.
• Limp mode: Powertrain protection strategy activated to prevent potential overboost events.
• Poor fuel economy: Efficiency loss due to altered boost control and conservative fueling strategies.
• Related DTCs: Additional sensor/reference/ground or boost-control related codes may appear alongside P2390.

Common Causes

• Short to power on the signal circuit: Damaged insulation or chafed harness allowing the boost sensor control/signal line to contact a voltage feed.
• Open or high-resistance ground: Poor ground path for the sensor causing the control/signal to be pulled high relative to the module.
• Reference voltage fault: Reference feed to the boost sensor stuck high due to a wiring short or internal module issue (varies by vehicle design).
• Connector issues: Corrosion, moisture intrusion, terminal spread, poor pin fit, or partial disengagement at the boost sensor or module connector.
• Harness routing damage: Pinched, melted, or rubbed-through wiring near hot components or brackets leading to unintended voltage on the circuit.
• Sensor internal electrical fault: Boost sensor electronics biased high or internally shorted, driving a high input to the control module.
• Shared-circuit interference: Another sensor/actuator sharing a reference/ground splice backfeeding voltage onto the boost sensor circuit (splice packs vary by vehicle).
• Control module driver/input fault: Rare; an internal fault in the powertrain control module input stage interpreting or pulling the circuit high (verify all external causes first).

Diagnosis Steps

Tools typically needed include a scan tool capable of reading freeze-frame data and live data (including boost/MAP-related PIDs where applicable), a digital multimeter, and access to vehicle-specific wiring diagrams and connector pinouts. A back-probing method, terminal inspection tools, and basic hand tools help. If available, an oscilloscope can help capture intermittent spikes during a wiggle test and while driving.

1. Confirm the DTC and capture data: Verify P2390 is present. Record freeze-frame, pending/history status, and any companion codes (especially other sensor reference/ground or boost-related electrical codes). Clear codes and see if P2390 returns immediately or only after a drive cycle.
2. Check for obvious electrical/connector faults: With the key off, inspect the turbocharger boost sensor connector and harness for broken locks, moisture, corrosion, bent pins, or terminals pushed back. Repair obvious issues before deeper testing.
3. Inspect harness routing end-to-end: Follow the harness from the boost sensor toward the control module and any intermediate junctions. Look for chafing, pinch points, heat damage, or contact with sharp edges. Pay special attention to areas where the harness is tied down or passes near hot surfaces.
4. Verify the concern in live data: Key on/engine off and at idle (as applicable), observe the relevant boost sensor PID(s). A “high” electrical condition often appears as an implausibly high, fixed, or non-responsive reading. Log data while gently moving the harness to see if the signal changes abruptly.
5. Perform a wiggle test with monitoring: While watching live data (or an oscilloscope if available), wiggle the connector, sensor pigtail, and harness at multiple points. If the reading jumps, drops out, or the code sets during movement, suspect poor terminal tension, broken conductors, or intermittent shorts.
6. Check reference voltage integrity: Using wiring diagrams, identify the sensor reference circuit (if equipped). With the connector unplugged, measure the reference at the harness side and compare to service information. If the reference is too high or unstable, isolate whether it is affected by other sensors on the same reference by unplugging them one at a time (varies by vehicle).
7. Check ground quality with voltage-drop testing: Load the circuit as appropriate and perform a voltage-drop test on the sensor ground path between the sensor connector ground terminal and the battery negative or known good ground. Excessive drop indicates resistance in wiring, splices, or ground points that can contribute to a high-input condition.
8. Check the signal/control circuit for short-to-power: With key off and connectors disconnected as required (sensor and module side as directed by service information), test for continuity between the signal/control circuit and known power feeds. Any continuity suggests insulation damage or backfeeding through a shared splice/component.
9. Check for opens/high resistance in the signal and ground circuits: Measure circuit continuity end-to-end and inspect for high resistance across terminals and splices. Perform a pin-fit/tension check where accessible; poor pin fit can create intermittent opens that bias a circuit high.
10. Substitute components only after circuit checks: If wiring, connectors, power, and grounds test good, suspect the boost sensor internal electrical fault. If a known-good sensor does not resolve the issue and all external circuits remain verified, consider a control module input/driver fault (rare) and follow vehicle-specific confirmation steps.
11. Verification drive and final scan: After repairs, clear codes, run the monitor/drive cycle appropriate for the vehicle, and review live data logs for stable operation. Recheck for pending codes and confirm P2390 does not return.

Professional tip: When chasing a “circuit high” fault, prioritize finding how voltage is getting onto the signal (short-to-power, backfeed through shared splices, or a missing ground). Intermittent cases are often terminal tension or harness rub-through; reproduce the fault with live-data logging during a controlled wiggle test, then pinpoint the exact section by isolating harness branches and connectors one at a time.

Possible Fixes & Repair Costs

Repair costs for P2390 vary widely because the fault can be caused by anything from a minor connector issue to harness repairs or a sensor/control replacement. Total cost depends on diagnostic time, parts required, labor access, and whether additional wiring damage is found.

• Repair wiring faults: Restore damaged insulation, repair short-to-power conditions, and correct routing where the harness may be chafing or pinched.
• Service connectors: Clean corrosion, dry moisture intrusion, correct terminal tension/fit, and ensure full connector seating and proper lock engagement.
• Restore power/ground integrity: Repair shared power feeds, grounds, or splices affecting the turbocharger boost sensor control circuit; confirm low resistance and stable connections under load.
• Replace the affected sensor or control component: If testing confirms the turbocharger boost sensor or its control circuitry is outputting an incorrectly high signal due to internal failure, replace only the verified faulty part.
• Repair reference/signal circuit issues: Correct opens in ground return, high-resistance joints, or unintended voltage backfeed that can drive the signal/control line high.
• Address water intrusion: If inspection shows moisture in the connector or harness, repair the source of intrusion and any compromised wiring/terminals.
• Control module-related repair: If all external circuits and components test good but the command/sense line remains high due to an internal driver or input fault, follow service information for confirmatory tests before replacing/reprogramming as applicable.

Can I Still Drive With P2390?

You may be able to drive short distances if the vehicle feels normal, but P2390 indicates a “control high” electrical condition that can trigger reduced power and unstable boost control depending on vehicle strategy. If you notice severe loss of power, surging, abnormal engine behavior, warning messages affecting drivability, or any safety-related concerns (such as stalling), do not continue driving—have it diagnosed promptly.

What Happens If You Ignore P2390?

Ignoring P2390 can lead to ongoing warning lights, reduced performance modes, inconsistent boost control behavior, and potential additional fault codes as the system compensates for an implausible high electrical signal. Continued operation with an unresolved circuit fault can also worsen connector damage, heat-related harness deterioration, or intermittent failures that become harder to pinpoint.

Last updated: February 16, 2026

Vehicles Commonly Affected by P2390

• Turbocharged gasoline engines: Vehicles using boost control strategies that rely on a dedicated boost sensor control circuit.
• Turbocharged diesel engines: Applications with electronically monitored boost sensing/control circuits.
• Vehicles with high under-hood heat: Platforms where harnesses and connectors are exposed to elevated temperatures near the turbocharger.
• Vehicles with known harness flex points: Designs where the engine harness moves with engine torque and can chafe over time.
• Vehicles frequently driven in wet or corrosive environments: Conditions that increase connector corrosion or moisture intrusion risk.
• High-mileage vehicles: Aging insulation, terminal fretting, and ground degradation can increase circuit-high faults.
• Vehicles with recent engine/turbo service: Disturbed connectors, pinched wiring, or misrouted harnesses after repairs can contribute.
• Vehicles with aftermarket electrical accessories: Added wiring that backfeeds voltage or alters shared grounds can influence sensor control circuits.

After repairs, confirm the fix by clearing DTCs, performing a careful road test under varied load conditions, and rechecking for pending or stored faults to ensure the turbocharger boost sensor control signal remains stable.