A picture of a car which I will look at next weekend (mailed by the owner). We see a Stromdieb (even the dictionary don’t know the translation. Some kind of cutting connector, the blue thing with the cables). Some advise:

• Do not use these things. They either don’t cut the insulation propably or the cut most of the copper inside. In either way that makes them a very reliable source for connection problems which (especially with 12V) have a tendency to produce fire. Especially especially if they are used very close to the alternator (on top of it to be precise) which maybe means there is no fuse…
• Engines tend to get hot. Do use components which are heat resistant. (These things aren’t)
• Do not connect red and blue wires. Red is commonly used for + and blue for -. First of all it looks stupid and it secondly it will confuse and annoy anyone who will ever work on the car.