BMW DTC P142B – Crankcase Ventilation Heater Relay Circuit Low
DTC P142B meaning on BMW
The DTC P142B code on BMW vehicles indicates an issue with the Crankcase Ventilation Heater Relay Circuit being detected as low. This means that there is a problem with the electrical circuit related to the crankcase ventilation heater relay, which is responsible for regulating the temperature of the crankcase ventilation system.
BMW DTC P142B symptoms
Some common symptoms associated with the BMW DTC P142B code may include:
- Check Engine Light illuminated on the dashboard
- Reduced engine performance
- Increased fuel consumption
- Engine stalling or rough idling
BMW DTC P142B causes
The potential causes of the BMW DTC P142B code can vary, but some common reasons include:
- Faulty crankcase ventilation heater relay
- Short circuit or open circuit in the relay circuit
- Wiring issues or poor connections
- Defective crankcase ventilation heater
BMW DTC P142B seriousness
While the DTC P142B code may not cause immediate harm to the vehicle, it is important to address the issue promptly to prevent potential damage to the engine or other components. Ignoring this code can lead to reduced engine efficiency and performance.
How to diagnose DTC P142B on BMW
To diagnose the DTC P142B code on a BMW, a mechanic would typically perform the following steps:
- Use a diagnostic scanner to retrieve the fault codes stored in the vehicle’s computer
- Inspect the crankcase ventilation heater relay and related components for any visible damage or signs of wear
- Check the wiring and connections for any faults or loose connections
- Test the crankcase ventilation heater relay and circuit for proper functionality
How to fix DTC P142B on BMW
Depending on the root cause of the DTC P142B code, the following steps may be taken to fix the issue:
- Replace the faulty crankcase ventilation heater relay
- Repair any damaged wiring or connections in the relay circuit
- Replace the crankcase ventilation heater if found to be defective
- Clear the fault codes and reset the Check Engine Light
How to erase DTC P142B on BMW
To erase the DTC P142B code on a BMW, you can use a diagnostic scanner to clear the fault codes stored in the vehicle’s computer. Once the issue has been addressed and fixed, clearing the codes will reset the Check Engine Light and ensure that the code does not reappear.
Recommended tools & DTC Scanners for BMW
Best Diagnostic App for modern BMWs: BimmerLink
Recommended Bluetooth adapter for Bimmerlink: OBDLink CX
Cable adapter for Bimmerlink: Enet Cable USB Type C
For older BMWs we recommend: Autel AutoLink AL319 (2024 version)
Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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