Star Headlight & Lantern 7400 Star Lase - Manual (Page 13)

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Determining if the bar is properly grounded:
1. While the bar is turned on, using a test meter, measure the voltage from the base of the bar
itself to the negative post of the battery or a good chassis ground if the battery can’t be easily
reached. You may need to scrape away a bit of anodizing or paint in order to ensure a good
connection with the probe of your test meter.
2. If the difference shown is greater than .25 volts, then your ground is not sufficient.
3. If the ground is insufficient, locate the ground wire connection in your lightbar by removing the
top extrusion (see page 3), exposing the area where the wires enter the bar. The ground wire
is the large (10AWG) black wire found in the Power Wire Harness. Check the integrity of the
connection of the ground wire to both the terminal block inside the lightbar and at the other
end to the negative side of the battery.
4. While inspecting the ground wire connections you should also check that the wire itself is not
damaged. Carefully inspect the wire along its entire length, paying special attention to those
areas where the wire passes through any holes that may have sharp edges, which can
damage the wire, and the areas where the wire makes any sharp bends.
Checking the power to the terminal block
(Determining if the proper voltage is reaching your bar):
1. Locate the terminal block in your lightbar by removing the top extrusion and endcaps (see
page 3). After the harnesses enter the bar, the wires will be connected to the terminal blocks
with a number of small screws.
2. With the bar turned on (all control wires activated), use a test meter to test the voltage at the
terminal block, for each individual wire. A nominal 12.5 volts should be present (except for the
black wire, red w/green stripe, and purple wires). Low voltage can cause erratic flashing in
strobe heads or even complete failure of the heads. A minimum of 10 volts should be present
for the heads to operate properly. Low voltage can result in lowered intensity or even
complete failure.
3. Be sure to test each wire that comes into the terminal block for proper voltage.
4. Carefully inspect each wire in the terminal block. Check that the ends of the wires have not
frayed and shorted against one another or against the base. This may cause lights to operate
inadvertently or may result in the failure of lights.
Checking one non-working head:
If a problem exists in only one head, the head may be defective, or there may be an open
electrical connection or short in the mini harness.
1. Disconnect the mini harness from the back of both the faulty head and a working head.
Carefully lift them both out of the lightbar and place the faulty head in the location the working
head previously occupied.
2. Plug the mini harness that was formerly connected to the good head, into the back of the
faulty head.
3. Activate the wire/function that controls that particular head location in the lightbar (see pg. 2).
If the formerly faulty head now works in the new location, the problem lies in the other
mini harness (connected to the location that this head was formerly in). Verify this by plugging
the other head (the original good head you just unplugged) into the position that previously
had the non-working head. It should also fail in this position. If so, check connections at and
between the Connector Board and the faulty head. If necessary, replace the defective mini
harness.
If the faulty head still does not work, then the problem lies in the head itself. If the head
contains a halogen bulb, check that the bulb is still good. If the head uses a different light
source (i.e. LED or strobe), then the head must be replaced.