What Does P3429 Mean?
The PCM has detected an open circuit condition in the cylinder 4 exhaust valve control system. The control circuit is not completing the electrical path required for proper valve operation.
Common Causes
35%
Disconnected or loose connector at cylinder 4 exhaust valve solenoid
30%
Open circuit in wiring harness to exhaust valve control solenoid
25%
Failed exhaust valve control solenoid with open coil
10%
Corroded or damaged connector terminals
Diagnostic Steps
1
Step 1: Visually inspect connector at cylinder 4 exhaust valve solenoid for proper connection and damage
2
Step 2: Measure resistance of exhaust valve control solenoid; compare to specifications
3
Step 3: Check continuity of both power and ground circuits from PCM to solenoid
4
Step 4: Inspect wiring harness for breaks, cuts, or damage along entire routing path
5
Step 5: Test connector terminals for proper contact pressure and corrosion
Estimated Repair Cost
$150 - $900
Parts + labor, varies by vehicle and location
The PCM has detected an open circuit condition in the cylinder 4 exhaust valve control system. The control circuit is not completing the electrical path required for proper valve operation.
The most common cause of P3429 (Cylinder 4 Exhaust Valve Control Circuit/Open) is: Disconnected or loose connector at cylinder 4 exhaust valve solenoid
Typical repair costs for P3429 range from $150 to $900, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle can be driven safely but exhaust valve control will not function. May experience reduced performance and increased emissions.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P3429 to identify the root cause.
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Quick Info
Category
Powertrain
System
Variable Valve Timing / Cylinder Deactivation System
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
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