: Connect the red clamp to the positive (+) battery terminal first.
Here is a breakdown of the key information found in the manual for the Bosch Keo (Model KL 1206). Bosch Kl 1206 Manual
Charging lead-acid batteries produces explosive gases. Always operate in a well-ventilated area. : Connect the red clamp to the positive
Best practice: Always record current ECU settings and backup ECU memory (when possible) before programming or performing adaptations. Bosch Kl 1206 Manual