RainTracker RT-40A Manual

Rain Tracker RT-40A Troubleshooting Procedure:
External Component Applications
This procedure is for Rain Tracker installations that include external resistors and diodes. Generally, these applications do not apply
current directly to the wiper motor. Typically, they present resistances to a vehicle body computer or control module.
Following this procedure will you time time.
1. Check Rain Tracker getting power and ground
Use a multi-meter or test lamp. Unplug the Rain Tracker interface J1) so you can put the test probes into the connector.
Symptom Check
12 V Present? Go to step 2
No 12V If possible, check the ground with a multi-meter. It should be no more than a couple ohms from
the Rain Tracker ground black wire) to a good chassis ground. Such as the connection outside
metal sleeve of the cigarette lighter.)
2. Check how the system behaves in each o the manual modes.
With the Rain Tracker activation switch off:
Symptom Check
Manual off, slow, and
fast and wash work as
before
Go to step 3
Wipers run all the time Could be a damaged Rain Tracker interface module. See “Bypassing the Rain Tracker”, below.
Manual slow does not
work
Most of these installations have the resistor in parallel with the existing system, so the Rain Tracker does
not control manual slow. Be sure that you have not cut the MUX connection.
Fast speed is slower than
it should be
There is some wiring error that is shorting the wiper motor slow and fast windings together. This should
not happen in these applications.
Fast does not work You should not have cut or tied into any wire to control FAST... did you?
Wash does not work The Rain Tracker does not control wash. Did you cut a wire you should not have?
Wash comes on for no
reason
Some Ford systems default to this when a wrong resistor value is applied. Check the resistance values.
Check “Bypassing the Rain Tracker” below. If still having trouble, contact Rain Tracker.
Bypassing the Rain Tracker
If you are still having trouble with the system in manual modes, try this diagnostic: Remove the Rain Tracker interface module. In
most external component applications, the wiper system should behave just as it did from the factory. If it does not, there is come
problem with the interface wiring.
3. Veri y that the inter ace can make the wiper motor run—Pulse the Rain Tracker activation
switch.
With the ignition on, turn on the activation switch for a few seconds. Each time you do this, the wipers wipers should run slow once.
Symptom Check
Wipers run slow for
one wipe when you
pulse the switch
Go to step 4
I cannot hear a relay
click inside the Rain
Tracker interface module
when I pulse the wiper
switch.
You probably have a problem with the power, ground, or activation switch.
Check to see that the activation switch is working: there should be about 12V at the activation switch /
mode reader GRY wire) coming into the Rain Tracker.
Rain Tracker RT-40A Troubleshooting Procedure : External Component Applications
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I can hear a relay click in
the interface module, but
the wipers do not run.
●Check the wiring around the SLOW relay—the BLU and the GRN wires from the Rain Tracker,
and the components connected to them. Are they going to ground or +12V, as the drawing calls
for?
●Check the external component values. Resistors are not polarized and can go in the circuit in
either direction. By the far the most common problem installers have with this sort of wiper
system is using the wrong component values. Resistor color bands are tiny and hard to see.
Check them in circuit, ideally) with a multi-meter.
●Diodes are polarized and must have the colored band in the direction shown on the drawing.
●Check that you have identified the right wires to Tee into. This is especially important if there
are two of the same color wires in the vehicle. For example, two dark green wires coming
from the wiper switch assembly, as is the case in many GM’s.) You can check this with a
voltmeter:
●Unplug the Rain Tracker from 10 position connector connected to the vehicle.
●Connect the black voltmeter minus probe to the black ground wire at the Rain Tracker
connector. Pin 1)
●Place the voltmeter positive at the Rain Tracker connection that connects to a resistor.
●With the vehicle on, change the wiper switch settings. Verify that the voltage changes
when you change the switch. If it does not, you probably have the wrong wire. This
test also makes sure you have a good connection to the resistor.
●If the Rain Tracker installation calls for more than one resistor, make this test for each
of them.
Wipers pulse, but at
FAST instead of SLOW
speed
Check the component values—did you use the right one for each location?
Wash comes on for no
reason
Some Ford systems default to this when a wrong resistor value is applied. Check the resistance values.
4. Diagnosing Sensor problems.
•If you skipped straight to this step, go back and systematically go through the procedure from the beginning, eliminating more
common problems.
•The sensor adjusts itself to the windshield when it powers up. To be sure that it has done this, turn the ignition off and then on.
•Place the existing wiper switch in manual off, and activate the Rain Tracker system
•See how the system responds to a spray bottle or garden hose.
Symptom Check
System does not respond
to water at all.
Did you mount the sensor so that the double-stick tape wets out against the glass?
•The sensor will not see through the red release-liner tape—you must remove it.
•You cannot just tape the sensor against the glass without mounting it.
•The tape must be fully ‘wetted out’ appears black from outside the vehicle)—you cannot lightly
tack the sensor to the glass.
Wipers wipe every five
seconds, regardless of
rain
This is what the system does when the sensor is disconnected. So, check that the sensor cable was not
cut during installation.
Also, the cause could be one of the “Wipers Keep Wiping” issues below.
Sensor responds barely at
all.
Is the sensor mounted too far in the shade band? From the mid 90's on, most US vehicles come with
infrared-absorbing shade bands. The Rain Tracker sensor can be mounted on the edge, but not deeply
within, the shade band.
Is the windshield an infrared reflective type? These are rare! On some Chevy venture vans, 1995-2001.
You can see the yellowish coating ending near the edge of the windshield, and usually built-in antennas.
The windshield logo may read "Sun Gate"
Is the windshield more than 0.25" 6 mm) thick? These are used on some large RV's with single-piece
windshields. Not on any passenger cars, vans or light trucks.)
Wipers keep wiping
without water
A few follow-up wipes are normal. These are to clear water that might have blown off the hood but
might have missed the sensor.
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The Rain Tracker as well as the rest of the wiper system) works better with good wiper blades.
Extremely worn wiper blades will cause the system to over-wipe. In such cases, replace the blades.
On vehicles that wipe from the center out e.g. recent Chrysler vans) having the sensor too close to the
edge of the wipe pattern will make the system wipe too much. Center-out wipers are more prone to the
wipers making more follow-up wipes; it is more important to keep the blades clean.
The sensor will be fooled by vibration; if you tap on the sensor, it will run the wipers. Don’t tap on the
sensor. False wipes due to vibration / road bumps are almost always caused by an unsecured sensor
cable. Use a black cable tie to secure the sensor cable to the mirror mount.
If the vehicle engine is not running, the wipers can run so slowly as to cause the wiper blades to fool the
sensor. Try the test with the engine running.
Follow up wiping can be excessive under conditions just about the freezing. These conditions are rare,
and the Rain Tracker still should not cause smearing.
Wipers never completely
stop wiping-- very long
intermittent
If the wipers never completely stop, replace the wiper blades they were due for it, weren't they?). Clean
the area just over the Rain Tracker sensor, and polish the glass with a soft cloth.
Check each of the conditions listed above.
Rain Tracker does not
respond fast enough
Note that it is normal for the wipers to speed up and slow down over several seconds. Real rain storms
do not start or stop instantly. The Rain Tracker should respond appropriately to a real rain storm. With a
spray bottle demonstration, it will appear to respond too slowly.
Sensitivity too low Rain-X or car waxes can makes the sensor too insensitive. You can use Rain-X or any other hydrophobic
coating, but clean the area just over the Rain Tracker sensor, and polish the glass with a soft cloth.
Be sure the Rain Tracker coupler installation is reasonably free of air bubbles. No more than a few,
each a few mm in diameter. If you use our supplied anhydrous alcohol pad to install, you will get a
permanent, high-quality bond.)
If the sensitivity is not to the driver's liking, you may shift it up or down using DIP switch positions 1, 2,
and 3. See the user manual for the proper settings.
Sensor appears to
actually slow down with
more water
This can happen in installations with external resistors. Check to make sure that the external component
values are correct. This condition can be tricky to diagnose because it looks like a sensor problem. Use
an ohmmeter if possible.
Sensitivity too high If the sensitivity is not to the driver's liking, you may shift it up or down using DIP switch positions 1, 2,
and 3. See the user manual for the proper settings. Note that the Sensitivity code from the LED will not
change with DIP switch settings.
On vehicles that wipe from the center out e.g. recent Chrysler vans) having the sensor too close to the
edge of the wipe pattern will make the system wipe too much.
Could you have wired the activation switch to ground instead of to B+? If you makes this mistake, it
will put the system on in maximum, not default, sensitivity, and give LED code 1-9 or 2-9.
No amount of water will
make the system run fast
This model of Rain Tracker does not automatically make the wipers run fast.
Responds to water, but
Fast speed is slower than
it should be
There is probably some wiring error that is shorting the wiper motor slow and fast windings together.
For example, if the power diode YEL & WHT) from Rain Tracker not wired in place. Be sure to correct
this, as it wears the wiper motor out.
Wipers wipe for no
reason
False wipes should be rare. Sometimes the Rain Tracker will see the first droplets of water before the
driver notices.
On very hot, humid days, water can drip down from the air conditioning units of the vehicles ahead.
This can cause enough tiny drops to trigger the Rain Tracker. Also, there can simply be tiny droplets of
water in the air in extreme humidity—the Rain Tracker detects water droplets as small as about two one-
hundredths of an inch. Simply turn the Rain Tracker off under such conditions.
Wipers wiper when I
drive over bumps
Check to be sure that the sensor is securely snapped into the Rain Tracker coupler.
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This can happen if the sensor cable has a long way to go to reach the headliner, and is not secured.
Solution: secure the sensor cable to the mirror mount base with a black cable tie.
Wipers wipe when I tap
the sensor
Stop tapping the sensor. Properly installed, the sensor is immune to normal vehicle vibration.
Late First Wipe As with all rain sensors including those sold on new cars), there will be times when enough water has
hit the windshield that you would like the wiper to wipe, but none has yet hit the sensor. These cases
should be infrequent enough that they are easily ignored. The Rain Tracker is better in this respect than
most rain sensors in the new-car market.
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