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Upfitter Aux. Switches (RPO 9L7): 

NEW REVISION POSTED: Please refer to UI Bulletin #110g for important updated information.

Rear Lighting Connections:

Please refer to UI Bulletin #113 for more information.

Commonly Used Electrical Connections/Circuits:

If you’re looking for an Ignition HOT circuit or maybe you’re in need of a Vehicle Speed Signal or other in cab signals, please refer to UI Bulletin #115c

IMPORTANT New UI Bulletins

 Power Take Off (PTO) Operating Description and Application Guide.

Power Take Off installers...UI Bulletin #120 has just been posted to provide you with operational and set-up instructions for the ALL NEW 2015 PTO control system. Please refer to this important guide for setting up and use of the PTO on the new 2015 Cab/Chassis vehicles.


Improper Engine Block Heater (Option K05) Usage - Continuous Power

UI Bulletin #117 has just been posted to the Technical Bulletin page... This bulletin provides important usage information of the Engine Coolant Heater on diesel engines.  Please take a moment to review this very important informational update.

Upfitter Configurable Auxiliary Circuits

UI Bulletin #118 has just been posted to the Technical Bulletin page... This bulletin provides important usage information 5W4/9C1 upfitter provisioned circuits

SPECIAL ALERT Updated 1:00 PM 8/14

S.E. Michigan encountered record rainfall on Monday August 11th 2014 causing major flooding thoroughout the region. This flooding includes the GM Warren Technical Campus forcing it's continued closure of some facilities and limited access to others.  Please be advised that your inquiries and requests may be delayed as a result of these closures.



If when installing an after-market flasher module and the rear tail lamps do NOT flash as expected, the Body Control Module (BCM) will require reprogramming.  The reprogramming can be performed at your local General Motors dealership.     GM Dealers: refer to DCS Message #3437 dated November 6 2014 and/or Service Update Bulletin # 14677


For information on the 2015 Chevrolet Tahoe PPV please refer to the 2015 Chevrolet Municipal Technical Guide… You can find this guide on the Body Builders Manual page…Select Light Duty>2015>Police/Special Service Vehicles

For specific detail pertaining to the 9C1/5W4 wire harness go to Technical Bulletin 118 located on the Technical Bulletins page of this website. Select the Technical Bulletin tab, followed by the SHOW ALL button on the page, and select the bulletin (#118)

Telephone "Hotline"

Beginning March 1, 2015 we will no longer be accepting inquiries/requests via the phone line.

This change is being made to better serve you in providing the most accurate information in a timely manner. For all inquiries, please complete form provided via the "Contact Us/Request Data" link located at the top of the webpage.

Use of this form insures we have all of your contact information and can begin the process of quickly assisting you in your request.

2016 Model Year Body Builder Manuals


As many GM vehicles begin their 2016 Model Year production launches, we too begin to rollout our 2016MY Body Builder Manuals. Our commitment is to have the Body/Chassis sections available at the start of production, and then launch the Electrical sections. We will continue to add body builder manuals as each vehicle line begins its 2016MY production. Please continue to check back to see future manuals and other information that can support you in your upfits.

Rear Camera - Box Delete Pickups

Information on adding a Rear Vision Camera on 2015i Fullsize pick-ups is available. UI Bulletin 127 is now available online and can be found on our Technical Bulletins page.