Wiring — It is a system that connects all the electrical components of a car. The operation of headlights, sensors, fuel pump and starter depends on it. Corrosion often remains invisible, but it can gradually destroy even serviceable wiring. Slight oxidation at the contacts can cause failures that drivers mistakenly associate with electronic modules or the battery.
How exactly does electrical wiring corrosion occur?
Electrical wiring corrosion occurs due to a combination of moisture, oxygen, and electrical current. When water or condensate gets into the joints, an electrochemical reaction begins on the metal. On the outside, this manifests itself as a green or white coating that worsens conductivity over time.
In especially dangerous conditions - after washing the engine, getting melt water or operating on saline roads - the process is accelerated. Salt acts as a catalyst, and temperature changes cause microcracks in the insulation, through which moisture penetrates into the wire.
Corrosion often begins precisely in connectors, mass points, soldering and terminal compression points. There, the metal does not have a protective layer, so oxidation develops imperceptibly. Over time, the contact begins to heat up, the resistance increases, and even minor rust can cause the chain to break.
For example, moisture accumulates in the wiring of the taillights due to cracks in the rubber seals, and in the connectors under the seat due to condensation in wet weather. From the outside, the system may work normally, but the current passes with losses, and over time, this leads to failures in the operation of electronic modules.
Signs and symptoms of electrical wiring corrosion
The first signals are usually inconstant.
- Lights may flash from time to time, and random errors appear on the instrument panel.
- Sometimes the engine is difficult to start or stalls suddenly.
All this often seems to be a problem with the battery or alternator. For example, in many Volkswagen models, the cause of ESP system failures may be oxidation of the sensor connector under the seat. In old Japanese cars, the contacts near the battery often corrode, which leads to unstable electronics.
How to check and find problem areas
- First, it is worth conducting a visual inspection.
- Traces of greenish or whitish coating on wires or connectors are a sign of corrosion.
- If the problem is not visible, a multimeter will help: check the voltage and resistance in suspicious areas.
Corrosion can be hidden - under the insulation or at the junction of the wires. In such cases, partial disassembly and verification of each contact helps. Often problems are found in the trunk after water gets in or under the cabin mats, where condensation accumulates.
How to prevent destruction and repair wiring
Prevention is much more effective than repairs. It is worth periodically checking the contacts and covering them with a special anti-corrosion spray. For connectors, it is advisable to use dielectric grease, which repels moisture. Additionally, heat-shrink tubes can be used to seal the joints. After the winter period, it is useful to inspect the wiring at the bottom of the body and under the hood, where dirt and salt most often accumulate.
What should I do if the problem does arise? Repair of electrical wiring after corrosion depends on the degree of damage. If the oxidation is superficial, the contacts are cleaned with special agents for electrical connections or fine-grained sandpaper. After cleaning, it is important to treat the area with dielectric grease to stop re-oxidation.
When the conductors have lost their flexibility or have dark spots under the insulation, they need to be cut out and replaced with new sections. Such work is carried out using soldering or crimping joints followed by hermetic closure with heat-shrink tubes. It is unacceptable to twist the wires manually - the contact will quickly oxidise again.
In cases where the entire tourniquet is damaged, it is more advisable to replace it completely. For example, in the trunk or under the hood, where the wires pass near sources of moisture, partial repairs often give only a temporary effect.
After restoration, it is worth testing with a multimeter to check the resistance and voltage drop. If the values are normal, the repair site is additionally covered with a sealant or anti-corrosion spray. This approach ensures reliable contact and prevents re-destruction due to moisture or temperature changes.
Corrosion of electrical wiring develops slowly, but its consequences can be costly. The loss of contact in one connector can stop the operation of important systems. Therefore, regular inspection and prevention is the best way to protect yourself. Even if an electrical failure seems like a trifle, you should immediately look for the cause - perhaps it is hidden in the oxidised wire under the insulation.