Malfunctioning washers on diesel touring vehicle - assistance needed.

[LimeLing]

(Touring with a diesel engine)

Does anybody know of a prevalent malfunction that causes washers to stop working?
With the ignition turned on, I have electrical power to the two-pin connection. I have purchased a new pump that is installed in the washer bottle, but unfortunately, the issue still persists and there is no success. The rear one is also non-functional.

Is it normal to hear the pump operating while the ignition is on and the right hand stalk is pulled? The windscreen wipers activate as anticipated, but, there is no audible sound from the pump and no liquid spray is emitted.

There is a second connection that is similar to the first one, except it has a cover on it. The automobile had extensive modifications and repairs some time ago, and has been mostly inactive since then due to the engine replacement. Consequently, it is possible that certain components may have been inadvertently interchanged.

The only plausible explanation I can conceive of is that the wiring between the fuse box and the pump is faulty.
All suggestions are welcome.

[Authorce]

Typically, you can audibly perceive the operation of the pump. However, it is advisable to inspect the filter for any obstruction caused by black, viscous substance. Inspect the filter/seal by removing the pump and then extracting the seal for examination.
While you are there, connect a voltmeter to the wire pins and check for the presence of voltage while the washers are in operation.

[LimeLing]

Thank you. Verified the presence of electricity to the pump, which is functioning properly. I had already removed the bottle and found no obstructions in either the bottle or the pipes.

[Syncephe]

"There is an additional connector that is identical to the one reaching the pump motor, but it is covered with a cap." The automobile had extensive modifications and repairs some time ago, resulting in it being mostly out of commission. During this period, the engine was also replaced, which may have caused some confusion or mixing up of components.

The first step I would do is to examine...

[LimeLing]

Yes, I did. There is no electricity supply to that particular one, and it was not the one that I first removed. (I fail to get why the previous owner would mistake the two, especially considering that one of them is covered by a cap.)

[NarrativePsych]

When my vehicle's washers stopped functioning, it was discovered that the bottom of the washer bottle had gotten obstructed by 'sludge' from the fluid within. This was a result of my seldom use of the automobile, which led to the washers not being used. After removing, cleaning, and refilling the bottle washer, everything was satisfactory.

[LimeLing]

Unfortunately, that is not the case. The inside of the washer bottle is immaculate. The fluid lines leading up to the jets are also present. Since I am unable to perceive any sound coming from the pump, it is plausible to conclude that the issue lies either with the pump itself or with a component before it.

[Authorce]

If the pump plug has power, then the only possible cause is the pump itself. Did you check both pins in the socket to ensure that the earth connection is there as well?
The polarity should also be switched depending on whether the front or rear washers are being operated.