Troubleshooting my MIER DA-500 Driveway Alarm System

Here are some suggestions to determine if your Drive-Alert System requires service. Most problems can
be readily isolated.
Intermittent, constant alarm
When an intermittent or constant alarm occurs, disconnect the plug from the 120-volt power. Open the
door to models DA-503 or DA-504 and disconnect the red and black sensor wires from the terminal strip.
Reconnect the 120-volt power. Observe the LED (red light – No. 2) on the circuit board identified as Noise
Blanker. It will remain on for about 1 minute, then go out. Thereafter, the alarm should be silent. DO NOT
TOUCH the R and B terminals during this time. If the alarm sounds as soon as this LED goes out, the
unit is malfunctioning and should be returned for repair.
When no alarm sounds
When no alarm sounds, check the LED (red light – No. 1) on the printed circuit board identified as DriveAlert Control Panel Board. If it does not glow, check the 1 amp fuse on the circuit board – near the black
relay. If open, replace with another 1 amp fuse. If red light remains out, check for AC power at the AC
outlet. If power is present, the unit is malfunctioning and should be returned for repair.
Checking sensor probe
To check the sensor probe for false alarm conditions, disconnect the red, black and silver wires from the
terminal strip. Use an ohmmeter to measure sensor coil resistance. Measure red to black leads, which
should read 700-1200 ohms. When two or more probes are in series add the resistance for the correct
value. Two probes would equal 1200 ohms. If resistance is correct, measure the leakage resistance from
the red lead to the silver (shield) lead. The meter should show infinite resistance as though no connection exists. Use a high resistance ohmmeter. If analog, x 10,000 range. If digital, unit should have a 40 million-ohm capability. Any meter deflection that shows indicates moisture has entered the cable through
a break in the outer insulation and the red and black conductors. Digital meters and analog meters with a low range may not indicate a problem when the leakage resistance is 2 to 10 million ohms (this can cause false alarms).
Checking remote modules
If one of the remote modules, a Remote Chime, Lamp Module, or Wall Light Switch does not activate
when the Drive-Alert senses a vehicle, generally the problem is the codes are not properly set. First,
make certain that the Unit Code and House Code on the remote device is set to correspond with those
same codes on the Powerhouse Interface in the Master Control panel. If you have the DA-504 DriveAlert, the Powerhouse on the left controls the transmission of signals to Lamp Modules and Wall Light Switches. The Powerhouse on the right controls signals to the Remote Chimes. Secondly, make certain
the Input and Mode on the Powerhouse Interfaces are set correctly – the one on the left should be Input A
and Mode 1, and the one on the right should be Input A and Mode 3.