What this code means

1: Before switching the LC on, the software checks the power bridge: it turns on alternatingly the Low side Power Mosfets and expects the phases voltage to decrease down to -BATT. If the phases voltage do not decrease, this alarm occurs. Cause 2: This alarm may occur also when the start up diagnosis is overcome, and so the LC is closed. In this condition, the phases’ voltages are expected to be lower than 1/2 Vbatt. If it is higher than that value, fault status is entered.

Applies to: ZAPI ACE0 / COMBIAC0 controller.

Possible causes / checks (from the source)

A) If the problem occurs at start up (the LC does not close at all), check: - Motor internal connections (ohmic continuity) - Motor power cables connections - If the motor connection are OK, the problem is inside the controller B) If the problem occurs after closing the LC (the LC closed and then opens back again), check: - Motor connections - If motor phases windings/cables have leakages towards truck frame - If no problem are found on the motors, the problem is inside the controller

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