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 of 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. Verify that the interface 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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Last Revised: 08/01/08
