Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with a part of the car that helps keep the engine clean. It's like when a heater in your house doesn't work because the switch is broken.
The P142B code indicates that the Engine Control Module (ECM) has detected a low voltage condition in the crankcase ventilation heater relay circuit.
The crankcase ventilation heater is responsible for preventing the buildup of moisture and ice in the crankcase ventilation system. The relay controls the power supply to the heater. A 'Circuit Low' condition suggests that the relay is not providing enough voltage to the heater, which could be due to a faulty relay, wiring issues, or a problem with the ECM.
• Check Engine Light illuminated
• Poor engine performance
• Increased emissions
• Faulty crankcase ventilation heater relay
• Damaged wiring or connectors in the relay circuit
• Faulty Engine Control Module (ECM)
Crankcase: The part of an engine that contains the crankshaft.
Relay: An electrical switch that opens and closes under the control of another electrical circuit.
• Use a scan tool to check for any additional codes.
• Inspect the crankcase ventilation heater relay and wiring for damage.
• Test the relay for proper operation.
• Replace the crankcase ventilation heater relay if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scan tool
• Multimeter
• Relay tester
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Dodge Ram
• Regular maintenance checks
• Inspect wiring and connectors periodically
• Ensure proper functioning of the ECM
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional mechanic.
Repairs may be covered under the vehicle's powertrain warranty.
This code has been associated with issues in vehicles with complex crankcase ventilation systems, particularly in colder climates.
Moderate – This issue can lead to increased emissions and poor engine performance if not addressed.
Driving with this code may not be compliant with emissions regulations.
• Engine at operating temperature
• Vehicle parked in a safe location
The crankcase ventilation heater relay is typically located in the engine bay, within the fuse and relay box.
Q: Can I drive with a P142B code?
A: While you may be able to drive, it's not recommended as it can lead to increased emissions and engine performance issues.
Q: How do I reset the Check Engine Light after fixing the issue?
A: Use an OBD-II scan tool to clear the code after repairs are completed.
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