Contact resistance and oxidation

2004 Volvo C70 2.4 63SECTION Contact resistance and oxidation
Fig 1: Inspecting Terminals
GLL101078Courtesy of VOLVO CARS OF NORTH AMERICA.

In theory, the resistance across contacts, leads and terminals should be 0 Ω. However, there is always some resistance due to terminal oxidation.

If this resistance becomes too great the result will be a malfunction. The magnitude of the resistance before it causes a malfunction depends on the circuit load.

Checks: 

Cleaning female socket terminals and male pin terminals 

Fig 2: Apply Rust Solvent Spray Or Grease To Connectors
GLL101140Courtesy of VOLVO CARS OF NORTH AMERICA.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.