The battery terminal and starter wiring on our 1991 Volvo 240, with the B230 engine, is delightfully simple. By contrast, on my 1989 BMW 325i, there are multiple wires running from the positive terminal of the battery. I found out the hard way that, if any one of these comes loose, the BMW will not start and run.
Last Updated: 03/29/2016
Parts Group: Starter
This made me appreciate the simplicity of the Volvo design: one simple, thick, red cable is all that's attached to the positive battery terminal. This cable runs directly down to the starter. Via a metal eye or ring, the cable fits over a bolt-shaped electrical connector on the starter. Attached to the same bolt, directly next to the first eye or ring, is an identical-looking second eye or ring, attached to an identical-looking second red cable that in turn feeds the electrical power to the rest of the car. A simple 13mm nut fits onto the bolt-shaped electrical connector and keeps the two metal eyes or rings tightly in position.
A light-colored, thin wire with a female spade terminal slides onto the male spade terminal on the starter. This is for the current that energizes the solenoid and turns the starter motor on. There are two male spade terminals on the starter, parallel and next to each other. They are not the same size so it's easy to figure out which one to use. I don't know what the second spade terminal is used for; on our car it seems to never have been used, judged by the surface of the metal.
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