P1702 — Turbo Control Solenoid Circuit Malfunction

P1702 — Turbo Control Solenoid Circuit Malfunction. A fault in the turbocharger / supercharger boost control. Short, gentle driving to a shop is usually possible. Typical causes: worn turbocharger, stuck wastegate or faulty boost control solenoid, boost leak in intercooler piping or hoses.

For Ford vehicles

transmission range sensor – intermittent fault

powertrain (engine/transmission)

Is it safe to drive?

Drive with caution Drive gently and avoid boost. The car will likely be down on power and may be in limp mode; ignoring boost faults can overheat the engine and destroy the turbo — a far more expensive repair.

How to diagnose with an OBD scanner

Read the code and freeze frame Connect an OBD2 scanner, confirm P1702 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
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.
Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the turbocharger / supercharger boost control for damage, corrosion, chafing or poor contact.
Subsystem check Run the module's actuator test for the turbo control solenoid if your scanner supports it — a component that does not respond to a direct command is confirmed faulty.
Subsystem check Pressure-test the intake piping for boost leaks — cracked intercooler hoses are the most common cause.
Subsystem check Command the boost control solenoid with a scanner and verify wastegate movement.
Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P1702 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for P1702 (parts and labor, USD, independent shop rates): Turbocharger replacement: $1,200–$3,500; Replace boost control solenoid or actuator: $200–$600; Repair boost leak (hoses, clamps, intercooler): $100–$400. Overall, fixing P1702 usually costs between $100 and $3,500. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

Will P1702 clear itself?

Sometimes P1702 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 P1702 mean?

What is the most common cause of P1702?

The most common causes are: worn turbocharger, stuck wastegate or faulty boost control solenoid, boost leak in intercooler piping or hoses.

What are the symptoms of P1702?

Drivers most often notice: significant loss of power, Check Engine Light on, limp-home mode, increased oil consumption.

Is it safe to drive with P1702?

Drive gently and avoid boost. The car will likely be down on power and may be in limp mode; ignoring boost faults can overheat the engine and destroy the turbo — a far more expensive repair.

When your vehicle's computer detects a problem with how it commands the turbocharger's boost system, it logs code P1702. This specific diagnostic trouble code means the engine control module has identified a malfunction in the turbo control solenoid circuit. The PCM performs regular self-tests on this circuit, and when those tests fail repeatedly under specific operating conditions, P1702 gets stored and the check engine light comes on.

Unlike codes that point directly to a wiring problem, P1702 tells you the self-test failed but doesn't immediately reveal whether the issue lives in the solenoid itself, its wiring, or even the control module driving it. This matters because you could waste money replacing a perfectly good part if you jump to conclusions. The ECM waits for the fault to appear multiple times before lighting up the dashboard, so a single glitch won't trigger the code. When it does set, the freeze frame data captures engine load, RPM, coolant temperature, and vehicle speed at the exact moment the problem occurred. Use that snapshot to recreate those conditions during your diagnosis.

The turbo boost system forces more air into the cylinders than atmospheric pressure alone would deliver, and the turbo control solenoid manages how much boost the system builds by controlling the wastegate. When this solenoid circuit malfunctions, the engine loses its ability to regulate boost properly, leading to noticeable performance problems and potential engine damage if the fault persists.

Symptoms of P1702

Noticeable reduction in engine power and acceleration
Check engine light illuminated on the dashboard
Vehicle enters limp-home mode with limited performance
Elevated oil consumption by the engine
Black smoke exiting the exhaust pipe during acceleration

Common Causes of P1702

The most frequent culprits, listed from most to least likely:

Internal failure of the turbo control solenoid or its actuator mechanism
Wiring problems such as damaged insulation, loose connectors, or corroded terminals in the boost control circuit
Control module driver failure or outdated software requiring a reflash
Worn or damaged turbocharger unit with bearing wear or blade damage
Stuck or binding wastegate preventing proper boost regulation
Clogged intake tract, exhaust system, DPF filter, or catalytic converter restricting flow
Boost air leaks in intercooler piping, cracked hoses, or failed clamps

How to Diagnose P1702

Work through these steps systematically before replacing any expensive parts:

Connect an OBD2 scanner and confirm P1702 is stored in the PCM. Record all freeze frame data so you know precisely what engine conditions triggered the fault—load, temperature, RPM, and speed.
Pull any related diagnostic trouble codes. Codes in the same system often point to the root cause. Check manufacturer TSBs for your specific make and model—many boost-related faults have published factory solutions or software updates available.
Inspect the wiring harness and electrical connectors at the turbo control solenoid. Look for chafed wires, broken insulation, corrosion buildup, and verify the connector seats securely with proper terminal tension.
If your scan tool supports actuator tests, command the turbo control solenoid to cycle. A solenoid that ignores commands and shows no movement confirms failure of that component.
Perform a boost leak test on the intake system. Pressurize the piping and listen for escaping air at the intercooler, hoses, and clamps. Leaks here produce symptoms identical to a failed solenoid.
With the scanner, command the boost control solenoid and monitor wastegate operation—mechanical movement should be visible or measurable. Finally, clear the code, drive the vehicle through conditions matching the freeze frame data, and verify P1702 does not reappear.

Repair Options and Costs for P1702

Address the cheapest and most common failures before assuming the worst:

Replace boost control solenoid or actuator: $200–$600
Repair boost leak (hoses, clamps, intercooler): $100–$400
Replace turbocharger unit: $1,200–$3,500

Diagnosing which component is actually faulty keeps your total bill at the lower end of that range. The turbocharger itself is rarely the problem—wiring faults and solenoid failures account for most P1702 codes.

Can You Drive with P1702?

Caution is the right call here. Your vehicle may feel sluggish, struggle to accelerate, or have entered limp-home mode to protect the engine. Running with uncontrolled boost or reduced cooling can cause the engine to overheat and accelerate turbo wear. Get this diagnosed promptly to avoid turning a $200 fix into a $3,500 turbo replacement.