Faulty exhaust valve control solenoid or actuator; Damaged or chafed wiring harness to the solenoid, causing a short to voltage; Corroded or loose electrical connector at the solenoid; Failed PCM driver for the control circuit (rare); Internal mechanical binding of the exhaust valve or rocker arm, overloading the solenoid; Oil sludge or debris blocking the solenoid's oil passages, leading to abnormal resistance

DTC codes / P34xx · Auxiliary emission controls / P3496

P3496Cylinder 12 Exhaust Valve Control Circuit High

Q: What does code P3496 mean?

Cylinder 12 Exhaust Valve Control Circuit High. P3496 indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the control circuit for the exhaust valve of cylinder 12, which is part of a variable valve timing or cylinder deactivation system. The PCM expects a specific voltage range when commanding the valve, and a reading above the threshold triggers this code.

P3496 indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the control circuit for the exhaust valve of cylinder 12, which is part of a variable valve timing or cylinder deactivation system. The PCM expects a specific voltage range when commanding the valve, and a reading above the threshold triggers this code.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaAuxiliary emission controls

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Rough idle or misfire, particularly when the engine is cold or under light load
Reduced engine power or a limp mode if the fault affects valve operation severely
Poor fuel economy due to improper valve timing or cylinder deactivation
Increased emissions, which may be detected during an inspection
Audible ticking or tapping from the valve cover area if the solenoid is stuck

Common causes, most likely first

Faulty exhaust valve control solenoid or actuator
Damaged or chafed wiring harness to the solenoid, causing a short to voltage
Corroded or loose electrical connector at the solenoid
Failed PCM driver for the control circuit (rare)
Internal mechanical binding of the exhaust valve or rocker arm, overloading the solenoid
Oil sludge or debris blocking the solenoid's oil passages, leading to abnormal resistance

How to diagnose and fix it

Verify the code with a scan tool and check for any related pending or history codes
Inspect the wiring harness and connector at the exhaust valve control solenoid for damage, corrosion, or loose pins
Measure resistance of the solenoid and compare to the manufacturer's specification
Check for short to voltage on the control circuit using a multimeter with the PCM disconnected
Test the solenoid with a bidirectional scan tool to command it on and off while monitoring voltage
If the solenoid fails electrical tests, replace it and clear the code
If the circuit and solenoid test good, diagnose the PCM or mechanical valve train as needed

What most technicians overlook with P3496

A short to voltage in the harness can be intermittent and only appear when the engine is hot or vibrating, so wiggle-testing the harness while monitoring live data is essential.
Oil sludge or varnish inside the solenoid often causes high current draw that mimics a circuit fault, so checking oil condition and maintenance history is a smart first step.
The code can be set by a failing PCM driver even when the solenoid and wiring test perfectly, so don't rule out the module until all other checks pass.
Cylinder 12 exhaust valve control is often part of a multi-cylinder system, and a single faulty solenoid can affect the entire bank's operation, leading to driveability issues beyond a simple check engine light.
After repairs, a relearn or adaptation reset may be required for the variable valve timing system to function correctly, and skipping this step can cause the code to return.

Can I keep driving with P3496?

You can usually drive the vehicle short distances to a repair shop, but avoid heavy acceleration or towing because the fault may cause misfires or reduced power. If the check engine light flashes or the engine runs very rough, stop driving and seek immediate service.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.