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critical Kickass

Error Code Er1 - Red LED Flash : Reverse polarity error

Reverse polarity error detected (as per detailed description).

? What Causes This

Incorrect connection of battery terminals (positive/negative), during diagnostics stage 1.

How to Fix It

Swap the positions of the positive and negative clamps on the battery. Ensure that red (+) connects to battery's positive terminal, black (-) to negative terminal. Unplug charger from mains power before making changes.

Source: page 22 of the official manual

From the manual

Manual page 22 — Kickass error Er1 - Red LED Flash : Reverse polarity error

This error code appears in:

Kickass Kachg1222