Product Manual
10
Troubleshooting
If the red OVERTEMP LED and the audible alarm come on, the unit has overheated, and it 
will shut down until it cools off sufciently. You may not have allowed sufcient space around 
the unit for cooling, or there may be too many devices connected to the output of the unit. 
Either reduce the number of devices connected to the unit, or reposition the unit for better 
cooling. If necessary, direct a stream of moving air over the unit. 
If the yellow LOW INPUT LED and the audible alarm comes on, the input voltage has 
dropped to below a usable level. 
If the LOW OUTPUT LED and the audible alarm come on, and the green OUTPUT ON LED 
is completely off, the output of the unit has been shorted out, or there has been an internal 
failure. Turn the unit off, disconnect all the loads connected to it, and turn it back on again. If 
it comes on normally, turn it off again, reconnect one load, and turn it back on. Continue recon-
necting loads until the short circuit condition returns. Turn the unit off, disconnect the faulty 
load, and reconnect it only after the fault is found and rectied. If the condition still exists 
even after all the loads have been disconnected, the unit is defective, and must be returned to 
the factory or an authorized service center for repair. 
If the unit will not turn on at all, check the input fuse. To do this, rst turn off the unit and 
disconnect the power cord. Next, remove the negative battery lead and cover the end with non 
conductive material such as tape. Repeat this with the other battery lead. This will prevent an 
accidental discharge from the battery. Remove the fuse and check it with an ohmmeter. If it is 
blown, replace it with a new one. If that fuse blows as well or the unit still will not turn on, it 
is defective, and must be returned to the factory or an authorized service center for repair. 
If the batteries are hooked up backwards the output fuses will blow. To change them follow 
the same procedure as for the input fuse. 
If both the input and output fuses are good and the unit still does not function it must be 
returned to the factory for servicing.










