B3987 Trouble Code

View B3987 obd/2 error code description and symptoms. B3987 engine photo

HO2S Sensor Circuit Malfunction (HO2S-11) During testing the HO2S Heaters are checked for opens/shorts and excessive current draw.
The test fails when current draw exceeds a calibrated limit and/or an open or short is detected. Short to VPWR in harness or HO2S. Water in harness connector. Open VPWR circuit. Open GND circuit. Low battery voltage. Corrosion or poor mating terminals and wiring Damaged HO2S heater. Damaged PCM.

As the engine heats up and combustion becomes easier and more complete, the PCM will command the idling control valve to increase the amount of air entering the engine to suit the changing conditions. However, when the load on the engine changes, say, when some electrical consumers or other systems are either turned on or off, the PCM adapts the signal voltage to the idle control valve to ensure that the idling speed remains stable, and at the RPM specified by the manufacturer.

B3987 Error Code Repair Process :

If your wiper wash/delay switch circuit open check engine light is illuminated, it's best to take it in for diagnostic testing, which can feel like a hassle. Because while the lights vary in appearance from vehicle to vehicle, all have the same basic meaning: There's a problem with the car's emissions system. The on-board diagnostics system B3987 and engine control unit are in charge of monitoring a bunch of different wiper wash/delay switch circuit open, and if they get a reading that's a little out of whack, up pops the check engine light.

B3987 is a kind of Body Trouble Code

Auto body problems aren't always easy to spot. Diagnosing auto body problems sometimes requires a little know-how. In this section you'll find articles dedicated to teaching you how to diagnose auto body problems.

Common Causes of B3987

A common cause of code B3987 is the failure of Wiper Wash/Delay Switch Circuit Open, but there are several other possible causes as well, such as ;

Exhaust tube
Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted
Faulty Variable Camshaft Timing (VCT) position solenoid
Three way catalyst converter Bank 1

B3987 code for all cars

You can view according B3987 DTC for your car model. We selected several models to see obd2 solutions click and view it.

+B3987 Mercedes Cls 300

+B3987 Porsche 917

+B3987 Chevrolet K-20

+B3987 Buick 90

+B3987 Cg 1200

Engine OBD 2 Codes website is a freeware resource center for engine trouble codes.

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