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Q: starting problems voltage surge

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The battery cable came loose. It has caused a voltage surge. The car has intermittent starting problems. What electronic component could the voltage surge have damaged. Thank you.

Overvoltage spikes can cause damage to any of the computers on the CAN bus which are involved with the vehicle starting system. However on the 540’s, in the e-box under the hood, the main relays are known for failure and can cause intermittent no start conditions. The relay should be checked to verify it is switching on the engine computer when the vehicle is started. If the engine computer does not come online the vehicle will not start. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the training and tools to survey the engine computer and main relay to diagnose and correct the intermittent no start issue.

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