HomeTrouble CodesP3437

P3437 — Cylinder 5 Exhaust Valve Control Circuitopen

Manufacturer-specificPowertrain (engine & transmission)

P3437 indicates an open circuit in the exhaust valve control solenoid for cylinder 5, commonly found in engines with variable valve timing or cylinder deactivation. The PCM detects a lack of electrical continuity in the solenoid circuit, preventing proper valve control.

Symptoms

What causes it — most likely first

1. Faulty exhaust valve control solenoid

The solenoid itself is the most common failure point; internal open circuit or mechanical binding can trigger the code.

2. Damaged or corroded wiring/connector

An open or high-resistance condition in the harness between the PCM and the solenoid, often due to chafing, heat damage, or corrosion.

3. Poor electrical connection at solenoid

Loose pins, bent terminals, or moisture intrusion at the connector can cause an intermittent or permanent open circuit.

4. Engine control module (PCM) failure

A failed PCM driver circuit is a rare cause, only plausible after all other wiring and component checks pass.

How it's diagnosed

  1. Scan for additional related codes (e.g., misfire, other cylinder valve control codes) to narrow the issue.
  2. Visually inspect the wiring harness and connector for cylinder 5 exhaust valve solenoid for damage, corrosion, or loose connections.
  3. Measure the resistance of the exhaust valve control solenoid; compare to manufacturer specifications (typically 10–30 ohms). An open circuit reads infinite resistance.
  4. Check for battery voltage and ground at the solenoid connector with the ignition on; if missing, trace the power/ground circuits.
  5. Perform a bidirectional solenoid test with a professional scan tool to command the solenoid on/off and verify circuit integrity.
  6. If all previous steps pass, test the PCM output by backprobing the appropriate pin; only replace the PCM if a failed driver is confirmed.

Code facts & related codes

SystemPowertrain (engine & transmission)
StandardizationManufacturer-specific (P1/B1/C1/U1)

Frequently asked

Can I drive my car with code P3437?

You may be able to drive short distances, but the engine may run rough, lose power, or misfire, potentially damaging the catalytic converter. It's best to diagnose and repair promptly.

Is the exhaust valve control solenoid always the problem?

No, but it is the most common cause. Wiring issues and connector problems are also frequent. The PCM is rarely at fault; always rule out simpler causes first.

Do I need to replace the PCM for this code?

Almost never. Many drivers are told to replace the PCM, but that is usually incorrect. Only after thorough testing of the solenoid, wiring, and connections should the PCM be considered, and even then it is uncommon.

Will clearing the code fix the problem?

No. Clearing the code only resets the Check Engine Light temporarily. If the underlying open circuit remains, the code will return as soon as the PCM runs its monitor.