Posted 2011-05-30 7:56 AM (#134415) Subject: Brake controller troubles ......
New User
Posts: 1
Anybody besides me have troubles with a Tekonsha P3 digital controller? I am on my second one since September. They have just gone to locking up and going crazy. At first when it starts I can unhook it and reset it and it's fine. But then back to locking up. Trailer wiring has been tested and can't find anything wrong with the truck (08 dodge 3500 diesel).
Posted 2011-05-30 2:29 PM (#134417 - in reply to #134415) Subject: RE: Brake controller troubles ......
Member
Posts: 9
Location: Harpers Ferry, WV 25425
Many things could be causing your problems. It could be that you just got a defective controller. Two bad ones in a row is unlikely. It could be a problem with your truck's alternator.
Digital devices need to be powered by direct current (DC). Your vehicle's alternator produces alternating current (AC) that is rectified to pulsating DC. If the alternator has a problem, such as a shorted or open rectifier, or a shorted field winding, the alternator can produce a larger-than-normal AC voltage. To a digital device, the AC voltage, can interfere with the device's normal operation, causing locking up, or random malfunctioning.
Here are some web pages that explain how to check your charging system for excessive AC ripple. You basically check the vehicle's 12 volt system voltage's AC level using a multimeter.
Another check you can make, using your P3, is in the trouble shooting mode, set it to monitor the supply DC voltage. With the engine NOT running, it should show battery voltage of 12.6 volts or so, and be stable.
Next start the engine and read the supply DC voltage. It may bounce some, but only in the last digit (to the right). If the alternator has problems, you should see it jump up and down by a few tenths of a volt, indicating a problem.
The best check you can make is to look at your vehicles 12 volt system voltage with an oscilloscope. It should have the "picket fence" pattern illustrated in the links above if the alternator is OK. If not, it will show the jumpy pattern indicating a problem.
Another check you can make is to try to exercise your P3 and trailer brake system with the engine OFF, and the ignition on. If you can apply the brakes many times and make other adjustments to the controller in this situation, it would tend to confirm that the problem is in the alternator system. If the unit locks up or fails to perform properly with the engine off, there is something (probably) wrong with the controller.
Good luck, sounds like an interesting problem.
PS: Are any of your other vehicle's electronic devices malfunctioning? Lots of static in the radio? Could be confirmation of too much AC.
Posted 2011-05-31 1:58 PM (#134440 - in reply to #134415) Subject: RE: Brake controller troubles ......
Elite Veteran
Posts: 800 Location: Tenn/Ala.
Most of the chain type Auto Parts stores use a Bear ARBST tester to check alternators on the car in their parking lot. Takes about a minute. It can detect many charging pattern abnormalities. May be worth a quick drop by an OReillys, Auto Zone, Advance, etc.
Posted 2011-06-01 9:52 PM (#134474 - in reply to #134415) Subject: Installation Angle is important
Expert
Posts: 3853 Location: Vermont
Although the Tekonsha Prodigy does not require exact leveling for proper operation, the controller must be mounted between 0 and 70 degrees in order to function correctly. To determine whether or not the mounting angle may be affecting the performance of your Prodigy brake controller, inspect the controller itself to make sure the front of the controller is sitting at an angle in the acceptable range. If not, make adjustments to the mounting bracket to correct the installation angle.
Brake controller troubles ......
