If you do a search there are plenty of threads on earth points. They rust as the earth strap is steel + you get contact corrosion when two different metals touch. Earth point may look ok but need to be removed and cleaned. Sometimes the bolt can shear. The earth behind the nearside headlight and the strap from the engine to the chassis are the 2 that come up most often. I suspect due to vibration and exposure to the elements.
Here is a thread with photos and a diagram of the earth points. The diagram has 12 earth points but not all are labelled.
Attached are pictures for the Earth Points on the A2 :cool: NOTE: 1.6FSi Owners I have found that these cables are faulty in 3 cases (all on 2003 models!). It appears that the cable is clean at ends and makes good contact onto body, but if you look under the sleeve, it has corroded to the...
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