P1B4B Mercedes Clk Diagnostic Trouble Code

P1B4B Mercedes Clk code definition:
P1B4B is a kind of OBD-II Diagnostic P-Powertrain Diagnostic Trouble Code for Mercedes Clk.

P1B4B Mercedes Clk is described as Oxygen Sensor Circuit No Activity Detected Bank 2 Sensor 1. This code appears when the PCM (powertrain control module, also known as ECM or engine control module in other brands) remains at or close the 0.450 set voltage point. So if the problem persists despite of your diagnosis, then you should never hesitate to take your vehicle to your dealer or to a qualified mechanic.

Symptoms

Symptoms of a P1B4B Mercedes Clk diagnostic trouble code may include:

Faulty PCM
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Poor acceleration
Engine surge

Possible Causes :

Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
An air leak forward of the DPF will change the sensor readings resulting in the code
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.

Common Misdiagnoses

Vehicle Speed Output Circuit Problem
Cruise Control Servo Indicates Low Problem
A/C System High Pressure High Temperature Problem
PCM Stack Overrun Problem
Transmission Control Module Reprogrammable Memory Problem

Repair Processes :

Look for rubbing, scraping, bare wires, worn spots or melted plastic connectors. Pull the connectors apart and carefully look at the terminals (the metal parts) inside the connectors. Find out what kind of system you have and verify that voltage to the fuel level sensor is present at the fuel pump wiring harness.

Process Tips

Diagnostic trouble code P1B4B Mercedes Clk is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before P1B4B Mercedes Clk.

Fortunately, P1B4B Mercedes Clk is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.