P3402 — Cylinder 1 Deactivation/Intake Valve Control Circuit Performance

For Ford vehicles

cylinder 1 deactivation/intake valve control circuit – range/performance problem

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

Read the code and freeze frame Connect an OBD2 scanner, confirm P3402 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 cylinder 1 deactivation/intake valve control for damage, corrosion, chafing or poor contact.
Subsystem check Measure reference voltage, ground and signal continuity at the component connector.
Subsystem check Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P3402 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for P3402 (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 P3402 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

Will P3402 clear itself?

Sometimes P3402 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 are the symptoms of P3402?

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

What does OBD2 code P3402 mean?

Cylinder 1 Deactivation/Intake Valve Control Circuit Performance (P3402): 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 control module driver fault, open or shorted wiring in the circuit, corroded, loose or damaged connector.

Is it safe to drive with P3402?

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 do I diagnose P3402 myself?

Start with a scan: confirm P3402, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the cylinder 1 deactivation/intake valve control, and verify the suspect component against live data before buying parts.

What does P3402 mean?

P3402 (Cylinder 1 Deactivation/Intake Valve Control Circuit Performance) is stored when self-diagnostics detect abnormal readings or behaviour of the sensor and actuator circuits. It belongs to the powertrain (engine/transmission) category.

P3402 refers specifically to cylinder 1. On inline engines cylinders are counted from the front (belt end); on V-engines the numbering depends on the manufacturer, so check the firing-order diagram for your exact model. Location matters for the repair bill: some cylinders require intake manifold removal, which adds labor time.

To set P3402, the control module compares live readings of the sensor and actuator circuits against calibrated limits, usually over several drive cycles. Alongside the code it stores a freeze frame — a snapshot of rpm, load, coolant temperature and vehicle speed at the moment of failure. Reading that snapshot first saves diagnostic time.

What causes P3402?

corroded, loose or damaged connector
control module driver fault
open or shorted wiring in the circuit
poor ground connection

Common symptoms of P3402

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

How to diagnose P3402

Connect an OBD2 scanner, confirm P3402 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
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.
Visually inspect the wiring harness and connectors related to the cylinder 1 deactivation/intake valve control for damage, corrosion, chafing or poor contact.
Measure reference voltage, ground and signal continuity at the component connector.
Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P3402 does not return.

How to fix P3402

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 P3402?

Repair cost depends on which component actually failed. Typical scenarios for P3402 (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 P3402 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 P3402?