Resistance measurement requires an appropriate circuit state and method. An ohms reading taken on a circuit that remains energised is not a reliable substitute for the manufacturer’s specified test.
Preserve the test conditions
Ask whether the relevant supplies were safely isolated and what remained connected. Owners should not disconnect high-voltage or restraint circuits to attempt this themselves. Stored energy and vehicle wake-up behaviour require the correct precautions.
The report should identify the two measurement points and expected criterion. A number without circuit state cannot establish a failed component. If a previous diagnosis relied on an uncertain resistance check, obtain a properly scoped reassessment before ordering a controller or modifying wiring based on that result.
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