| Indicator | Color | Function when lit |
| Power ON (PWR) | RED | AC power present |
| Abnormal Shutdown (SDN) | RED | Flashes shutdown has occurred. |
| Error Detection (EDT) | RED | Lit when battery not connected or less than 2 volts. |
| Charging (CHG) | YELLOW | Charger Status – Flashes when charging. |
| Charged (CHD) | GREEN | Lighted – Full Charged |
If any of the L.E.D.s flash in a pattern of ‘3-Fast-Flash, then off, 3-Fast-Flash etc, the charge cycle has
terminated prematurely. An abnormal charging condition was detected and charging stopped due to a Charge Error Condition. Refer to the following Charge Error Table for a description of the possible failure or condition.
| Condition | Flashing LEDs |
| LED 1 | LED 2 | LED 3 | LED 4 | LED 5 | |
| Batter voltage high | Off | Off | Off | Off | Flash |
| Battery Polarity Reversed | Off | Off | Off | Flash | Off |
| Output Overload | Off | Off | Off | Flash | Flash |
| Battery Pack Unbalanced-1 | Off | Off | Flash | Off | Off |
| Battery Pack Unbalanced-2 | Off | Off | Flash | Off | Flash |
| Excessive Charging Time-1 | Off | Off | Flash | Flash | Off |
| Excessive Charging Time-2 | Off | Off | Flash | Flash | Flash |
| Excessive Overload | Off | Flash | Off | Off | Off |
| Battery Testing – 1 | Off | Flash | Off | Off | Flash |
| Battery Testing – 2 | Off | Flash | Off | Flash | Off |
| Inhibit Control Defective | Off | Flash | Off | Flash | Flash |
| Battery Over Temperature | Off | Flash | Flash | Off | Off |
| Internal Over Temperature-1 | Off | Flash | Flash | Off | Flash |
| Internal Over Temperature-2 | Off | Flash | Flash | Flash | Off |
| External Over Temperature | Off | Flash | Flash | Flash | Flash |
| Mode-Selected Not Valid | Flash | Off | Off | Off | Off |
- Battery Voltage High. Charger’s DC cord set possibly connected to a battery pack with voltage higher than the output rating of the charger.
- Battery Polarity Reversed. Check output connector and ensure proper polarity. Remake connections.
- Output Overload. While charging, and, for example, under severe motor loading, charger may shut down. This error is not very likely to occur.
- Battery Pack Unbalanced-1,2. Caused by unbalanced battery condition. Example: some batteries are at a much higher state of charge than others. This may require replacement of the batteries. Refer to the Equipment’s Operators manual for instructions on servicing the battery pack.
- Excessive Charging Time-1,2. Occurs when charging took too long. Possible causes include: use of a battery load that is draining energy from the battery while the charger is trying to charge that same battery, aged or unbalanced battery cell conditions, etc.
- Inhibit Control Defective. Inhibit is supposed to be active, but it is not. Check Inhibit vehicle wiring. If correct, internal inhibit switch may have been overload – contact factory.
- Excessive Overload. In the unlikely event that a heavy load is placed across the battery pack while the charger is trying to charge the battery and the charger cannot keep up with supplying energy to both the battery and the load, and then the battery voltage will decrease. Further charging is terminated.
- Battery Testing. This error is only generated by one of two conditions found during the Pre-Qualification Test Stage.
- Condition 1: A severely discharged battery pack did not charge up to 10.5Vdc for 12v-system, or 21Vdc for 24V-system, within 3 hrs.
- Condition 2: A heavy load, applied, prevents charger from charging battery pack above 10.5Vdc for 12v-system, or 21Vdc for 24V-system.
- Battery Over Temperature. If an external Thermistor was installed, the charger ceased charging due to detecting a hot battery.
- Internal Over Temperature-1,2. Charger shut down due to an internal over temperature condition – check fan operation and remove blockages, if any.