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Being Prepared for TAC, Caller Preparedness - Contacting U.S. Technical Assistance (TAC) and Use of Strategy Based Diagnostics

Subject:Being Prepared for TAC, Caller Preparedness -- Contacting U.S. Technical Assistance (TAC) and Use of Strategy Based Diagnostics

Models:2009 and Prior GM Passenger Cars and Light/Medium Duty Trucks (including Saturn)
2009 and Prior HUMMER H2, H3
2009 and Prior Saab Vehicles

Attention: This bulletin pertains to the U.S. -- Technical Assistance Center. Service Managers / Directors -- It is important that the following information is reviewed with all Technicians.


This bulletin should be used in conjunction with the following documents:

    • "Being Prepared" -- Article 5.3.1 GM Policy & Procedures
    • "Strategy Based Diagnosis" -- refer to the General Information section in Service Information (SI)
    • Bulletin 01-00-89-010G which covers:
      • Customer Concern Verification
      • Comeback Prevention
      • Technical Assistance Form
      • Strategy Based Diagnostics
      • Intermittent Concern Diagnostics
      • Repeat Repair Log

In the effort of continuous improvement, TAC has reviewed their Strengths and Weaknesses identified through surveys of Service Managers/Directors and Technicians. Based on this information, beginning May 1, 2008 , TAC will implement changes relating to caller preparedness. These changes will enable TAC to provide more timely and consistent service, and reduce comebacks to the dealers. This focus will not impact the majority of the dealerships that are prepared.

Caller Preparedness:

Prior to May 1, 2008, approximately 93% of TAC callers are prepared prior to contacting TAC. Changes are being made to ensure 100% of callers are prepared prior to contacting TAC. Beginning May 1, 2008, when a caller is unprepared, TAC will request the caller utilize SBD before calling TAC back. This change will insure that the TAC consultants get the right information PRIOR to attempting any diagnosis.

Below are examples of NOT being prepared and will no longer be acceptable beginning May 1, 2008:

    • Caller cannot provide a VIN, R.O. #, mileage, # of times in or # of days down, etc.
    • Specifications and readings can only be referenced as "good" or "ok".
    • Caller states "I only need a case number".

Key Steps to Strategy Based Diagnosis:

It is important that technicians complete the steps of Strategy Based Diagnosis PRIOR to contacting Technical Assistance.

  1. Understand and verify the customer complaint.
  2. Verify that the vehicle is operating as designed.
  3. Perform preliminary checks:
  4.  - visual inspection
     - gather diagnostic trouble codes
     - review service history for repeat repair and clues
  5. Follow published diagnostic system checks.
  6. Check for bulletins, recalls and Preliminary Information (PI's).
  7. Diagnosis of DTCs.
  8. Isolate the root cause.

Being Prepared:

Technician preparedness is vital to provide accurate diagnosis and recommendations for repair. As of May 1, 2008, the following information will be REQUIRED at the time of the call:

  1. Have a completed work order including VIN and details about the Customer's concern.
  2. Be aware of the total amount of days down and times in for the current concern.
  3. Understand and attempt to duplicate the customer's concern prior to calling.
  4. Have all DTCs recorded and diagnosed including all value and measurements before calling TAC. i.e. Voltages, resistance, pressures, scan tool values, etc.
  5. Search all service information including all published diagnostic documents, flow charts, bulletins and PI's prior to contacting TAC. Be prepared to discuss the most relevant documents.

The General Motors Technical Assistance Center Phone Prompts are designed to get the caller to the appropriate group when calling. Recently, the phone prompts have undergone significant revisions to allow a technician to "speed prompt" to the appropriate diagnostic team and shorten the amount of time it takes to reach a TAC consultant.

The TAC Phone Prompt chart and Required Information graphic can be printed for use as a technician quick reference guide. The most up-to-date TAC phone prompt chart can also be accessed via the DealerWorld Service tab and by selecting Service Forms.

General Motors U.S. Technical Assistance Center Phone Prompt


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