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Information on Importance of Using GM-Approved Terminal Probe Test Kit (J 35616) to Diagnose Electrical (UBEC, BEC, Fuse Block, Electrical Center) Concerns

Subject:Information on Importance of Using GM-Approved Terminal Probe Test Kit (J 35616) to Diagnose Electrical (UBEC, BEC, Fuse Block) Concerns

Models:2005-2007 Buick Allure (Canada Only), LaCrosse, Rainier, Rendezvous
2005-2008 Cadillac XLR
2005-2008 Chevrolet Colorado, Corvette, Malibu,TrailBlazer, TrailBlazer EXT, TrailBlazer SS
2005-2008 GMC Canyon, Envoy, Envoy XL, Envoy Denali
2005-2008 Pontiac G6, Grand Prix
2005-2008 Saab 9-7X
2005-2007 Saturn ION
2007-2008 Saturn Aura

Attention: The purpose of this bulletin is to inform dealers to use caution when probing the top of bussed electrical centers (BEC) and stress the importance of using the proper GM-Approved Terminal Probe Test Kit (J 35616) to diagnose electrical concerns.


A recent warranty analysis was performed on the return of bussed electrical centers (BEC). The majority of the returned BECs had damaged terminals due to improper probing with standard multi-meter probes or paper clips. A small sample of the returned parts were considered to be actually warrantable due to insufficient terminal contact.

The female terminals used inside the BEC are made of a copper/brass alloy and may be easily bent when inserting inapproriate probes or test equipment into the top of the BEC.

Notice: Any time a terminal is probed, there is a risk of causing an open circuit at the terminal interface. Bending or twisting the male pins on relays during removal may also damage the terminals and cause an open circuit. If interface damage is suspected in the BEC, the complete assembly will have to be replaced.

Use the J 35616 GM-Approved Terminal Probe Test Kit and ensure the terminal test adapter choice is the correct size for the BEC terminal. Do not visually choose the terminal test adapter because some BEC terminal cavities may appear larger than the actual terminal in the cavity. Using a larger terminal test adapter will damage the terminal. Refer to the J 35616 GM-Approved Terminal Test Kit label on the inside of the test kit for the correct adapter along with the connector end view for terminal size. The J 35616-35 test probe is the correct test probe and should always be used.

Probing Electrical Connectors

Notice: Do not insert test equipment pins (DVOM, etc.) or paper clips into any connector, BEC or fuse block terminal. The wrong diameter of test probes can deform terminals. A deformed terminal may cause a poor connection, which may result in a system failure. Always select the appropriate terminal probe from the J 35616 GM-Approved Terminal Probe Test Kit when diagnosing electrical concerns.

Obtain diagnostic information from other areas:

    • Probe the tops of the Maxi-fuses or Mini-fuses.
    • Back probe terminals under the BEC. Refer to Probing Electrical Connectors in SI.
    • Disconnect the connector in the circuit being tested and probe the front of the terminals using the proper terminal test probes.
    • Probe the terminals at the BEC that mate to the harness connector.
    • Probe the opposite end of the harness connector away from the BEC.
    • If the system that is being diagnosed has a specified pinout or breakout box, it may be used in order to simplify testing multiple circuits quickly.

Probing Procedure Tips

Notice: When probing, it is important to use the correct terminal probe adapter. Failure to use the proper test adapter may result in damage to the terminal being tested and improper diagnosis.

    • The terminal probe tip should be inserted straight into the cavity and kept stable while testing.
    • Do not wiggle or move the terminal probe tip once it is inserted into the terminal.
    • The number of terminal probe insertions should be limited to one.

The J 35616 Terminal Probe Test Kit

The J 35616 Terminal Probe Test Kit is one of the most important essential tools in your dealership This set of terminal test probes contain all the different sizes and types of terminals used in the past and even now. The Terminal Probe Kit is constantly being updated with new essential probes, which are shipped directly to your dealership. Additional terminal test probe refills or replacement probes may be purchased from SPX/Kent-Moore at 1-800-GM-TOOLS (1-800-468-6657).