Express Down Window Wiring

Discussion in 'Electrical Systems' started by clay's70, Dec 27, 2017.

  1. clay's70

    clay's70 Moderator Staff Member Lifetime Gold Member

    I am kind of late to the party on this upgrade. I have wired a door with the following diagram:


    I have bench tested this using a DeWalt 12v battery and a 50amp battery charger. The
    window goes down and up, but I do not have express down. I picked 6 of the modules at the
    junkyard and all of them act the same.

    I even wired it using the Ford window module:


    I still get down and up but no express. I tried several of the Ford modules also.

    Any ideas on what I'm doing wrong? I have not tried hooking it up to an actual battery.
  2. 8pack

    8pack Veteran Member Lifetime Gold Member

    Aug 29, 2007
    Pittsburgh, PA
    Talk to Junkyardz28find......He is the resident expert on this stuff.
  3. clay's70

    clay's70 Moderator Staff Member Lifetime Gold Member

    8pack -- Thanks!

    Just found this on another sight:

    A battery charger, bench power supply, etc. will NOT test Express or other window control modules functions.
    You can run power window motors all day long on any 12 volt power supply (one from an old computer works great) but you can not test a module that automatically drives the window motor in this way.

    They all have built in feedback circuits to tell them when they have reached the end of their travel.
    These circuits require that they get a lot of amperage during movement.

    Then when that amperage increases (window is all the way up/down or caught on your arm.[​IMG] ) they shut off.

    A battery charger, etc. will not give them sufficient amperage, thus they think they are already at the end of travel (or caught on your arm).

    Not even a 400 amp battery charger.
    I have tried this with several different units.
    To fully test them on the bench I had to use a fully charged battery for a power source.
  4. clay's70

    clay's70 Moderator Staff Member Lifetime Gold Member

    Well, I hooked it up to a battery. Window is crazy fast up and down (because of the relays) but I still have to hold the button for down.
    8pack likes this.
  5. Jim Streib

    Jim Streib

    Apr 6, 2004
    Saint Louis, MO USA
    I have to wonder, does the module you have offer BOTH express up AND down ?. It seems to me, and this is from limited exposure to factory setups, is that GM only offered a one touch or express down. Even though you have the module wired in a way to get the windows to do express up, I would think the wiring could be changed to have the module do an express down but then loose the express up as the module might only be designed to do express one way operation.
    I'm not familiar with all of the factory setups but I know when I was installing alarm/security systems I used a lot of the Clifford Smart Window modules in vehicles and these modules worked with two power window assemblies and by adding this module the switches for each window could be momentarily used to begin that window up or down and if tapped again, would stop the window travel. It also had to be initially set to where the electronics inside would monitor the amperage draws to where if there was an obstruction in the windows travel, the power was cut to the motor and then stop the travel of the window glass.
    The Clifford modules could also be wired up to an alarm to where when the car was armed the windows if down would have them roll up all the way and then using auxiliary channels on the remote, one could roll the windows down with the alarm still active to vent out interior heat on hot summer days.

    Looking more at your situation, it looks like your window motors require them to be grounded and then have a dedicated 12V input to get the window to go one way and then when the power is removed from that input and put on the other wire, then the window goes the opposite way ?. Most newer cars use reverse polarity on the motors and are two wire and either do not need a dedicated ground off of the motor or require the motor to be grounded. I now wonder if there is a compadibility issue ?

  6. clay's70

    clay's70 Moderator Staff Member Lifetime Gold Member

    Jim, thanks for your reply, I've put this on the back burner till i have more time to work on it.

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