P1533 IMRC Solenoid Circuit Fault
The P1533 code indicates that the Powertrain Control Module (PCM) has detected an electrical fault in the solenoid circuit for the subsidiary throttle valve, commonly known as the Intake Manifold Runner Control (IMRC) valve. This means the PCM has identified an open circuit, short to ground, or short to voltage in the solenoid control wiring, preventing precise control of the intake manifold geometry.
01. Most Common Causes
- Faulty IMRC solenoid (internal failure)
- Open or short circuit (to ground or battery voltage) in the solenoid control wiring
- Loose, corroded, or damaged connector at the solenoid
- Stuck or mechanically blocked IMRC actuator/valve
- Internal PCM driver failure (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine performance, especially at low RPM
- Possible rough idle or hesitation during acceleration
03. Step-by-Step Diagnosis
Scan for codes and verify P1533 is present; check for additional related codes.
Visually inspect the IMRC solenoid connector and wiring for damage, corrosion, or loose connections.
Test the solenoid resistance with a multimeter; compare to manufacturer specifications.
Check for power and ground at the solenoid connector with the key on; verify PCM control signal.
If wiring and solenoid are good, test the IMRC actuator for mechanical binding or blockage.
If all else passes, suspect a faulty PCM driver (requires professional diagnosis).
1. Frequently Asked Questions
Is it safe to drive?▼
You can usually drive short distances, but expect reduced performance and fuel economy. Have it diagnosed soon to avoid potential drivability issues.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, depending on whether the solenoid, wiring, or actuator needs replacement. PCM replacement is rare and more expensive.