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http://www.usgear.cc/dc_install.htm
D-CELERATOR® Diesel Exhaust Brake
"SUPER-DUTY MODEL" OPERATING INSTRUCTIONS
NOTICE:
This device is not designed for use while the cruise control system of your vehicle is turned on.
The controls that operate your new D-Celerator® consist of two driver-interactive components. First is the pushbutton "on/off" switch. Second is the D-Feat device. The D-Feat device is connected to the use of your throttle so that when you depress the accelerator, your D-Celerator® is automatically disengaged. When you release the accelerator, the D-Celerator® begins to function again. The D-Feat device consists of a D-Feat wire or a Microswitch.
To engage the D-Celerator® just press the pushbutton on/off switch. With your foot off the throttle, the red light located behind the U.S. Gear logo will illuminate solid. This means that the D-Celerator® is braking. To turn off the D-Celerator® , press the on/off switch again and the red light will go out.
Once the D-Celerator® is on, you will also be able to control the operation of the exhaust brake by using your D-Feat device. To temporarily disengage the D-Celerator® , apply pressure to the accelerator. While the D-Feat device is operational, the red light on the pushbutton on/off switch will flash continuously. To reactivate the D-Celerator® , release the accelerator.
To achieve maximum braking horsepower once the D-Celerator® is engaged, shift to a lower gear and keep your RPMs up. If you need less braking assistance, shift to a higher gear or turn the unit off. Use the pushbutton switch to turn the D-Celerator® off if you are not accelerating your vehicle.
WARNING:
The D-Celerator® is designed only to assist your vehicle brakes. At no time is the D-Celerator to be used instead of, or to replace, your factory equipped vehicle wheel brakes.
The Cycle Feature is an exclusive self-maintenance characteristic of the D-Celerator® which you will notice when you turn your ignition to the on position. The red light on the pushbutton will flash for fifteen seconds after you turn the ignition on. Then the D-Celerator® will cycle on and off twice. You may bypass the Cycle Feature by pressing the accelerator during the fifteen seconds that the light on the pushbutton is flashing. CAUTION: Do not use the bypass feature on a consistent basis. Regularly canceling the cycle feature combined with a lack of use of the exhaust brake could cause damage to your D-Celerator® .
NOTE: Due to soot build-up, it may become necessary to re-lubricate the large butterfly pivot shaft bushings in the D-Celerator Diesel Exhaust Brake. We recommend that this service be performed on a regular basis according to use (normally every couple of years).