I built a DIY grounding kit per the MazdaSpeed instructions Canzoomer was kind enough to provide.

I forgot, what order do you connect the cables? The grounding points first then the negative terminal last? or the reverse? Obviously I diconnect the negative terminal before doing anything, but I want to make sure I have the order right.

Thanks

 

Tie in to the negative terminal last. This way if, during your installation, you happen to short the ground to something live, nothing with happen because the car's ground is disconnected and won't complete the circuit. Don't sweat it though, it is MUCH less of an issue with a grounding kit than it would be if you installing something on the positive side (where every metal surface could present a potential circuit circuit.

Oh - don't expect much of a difference, if any at all, from the grounding kit unless you are adding equipment that places a large demand on ground return. Kind of like those silly $50 speaker wires if you ask me (electrical engineer, 20 years).

 

I would agree in principle with Mr.w2aew, with the addition of "Do the battery ground FIRST, and LAST"

Once it is off the battery, you lose your radio presets etc, but if you remove the ECU's ground while the battery is still connected, there are still other paths to ground, it could ground itself thru some other componest, causing damage.

So, take the ground terminal off the battery, do all the other connections, then hook it back up last.

S