TCSC Top Issues This Week

TCSC Top Issues This Week

The Techline Customer Support Center (TCSC) is available to help dealerships with diagnostic and programming issues related to Techline Connect (TLC) and the Service Programming System (SPS). TCSC has now […]

June 11, 2025
Vehicle-Wide Programming Status Summary Now Includes All Control Modules

Vehicle-Wide Programming Status Summary Now Includes All Control Modules

The Vehicle-Wide Programming (VWP) feature in Techline Connect (TLC) has been updated with several enhancements in the latest software release. VWP, which allows multiple control modules to be programmed during […]

May 30, 2025
2025 Model Year Transmission Fluid Capacities Chart

2025 Model Year Transmission Fluid Capacities Chart

A new TechLink reference chart is now available covering transmission fluid capacities. The 2025 Transmission Fluid Capacities chart can be viewed under the Reference Charts menu or by selecting the […]

May 30, 2025
Key Fob Learning on 2025 Police and Special Service Vehicles

Key Fob Learning on 2025 Police and Special Service Vehicles

The 2025 Tahoe can be equipped with special service vehicle packages for police use (RPO 9C1) (Fig. 7; shown with aftermarket equipment) and special service use (RPO 5W4).   Fig. […]

May 30, 2025
May Service Newsletter from the Experts at GM TAC

May Service Newsletter from the Experts at GM TAC

The latest diagnostic assistance from the professionals at the GM Technical Assistance Center is now available in the May GM Technical Assistance Center (TAC) Newsletter. It covers a number of […]

May 30, 2025
First-Ever 2026 Cadillac VISTIQ Debuts

First-Ever 2026 Cadillac VISTIQ Debuts

The first-ever all-electric 2026 Cadillac VISTIQ (Fig. 1) is now in production and hitting dealerships. Slotting between the LYRIQ and new ESCALADE IQ in Cadillac’s EV lineup, the VISTIQ delivers […]

May 22, 2025
New Rear Heating/Cooling System Provides 3rd-Row Comfort

New Rear Heating/Cooling System Provides 3rd-Row Comfort

The 2025-2026 ESCALADE IQ/IQL and VISTIQ feature a first-of-its-kind rear cabin heating/cooling system (RPO C69) for 3rd-row passengers. The separate HVAC system, controlled by using the Front Command Center touchscreen […]

May 22, 2025
Troubleshooting Tips for the DCA-8000P Diagnostic Charger

Troubleshooting Tips for the DCA-8000P Diagnostic Charger

The GM DCA-8000P Diagnostic Charger – an Essential Tool for all U.S. dealerships – is the latest generation battery charger and tester from Midtronics that provides fast, accurate testing results. […]

May 22, 2025
New Part Number Released for Silverado and Sierra Half Shafts

New Part Number Released for Silverado and Sierra Half Shafts

A new half shaft part number has been released for 2019-2025 Silverado 1500 and Sierra 1500 trucks equipped with the Z71 Off-Road Suspension Package (RPO Z7X). (Fig. 20) The new […]

May 22, 2025
Remove Protective Films on Overhead Console During PDI on the ESCALADE IQ/IQL

Remove Protective Films on Overhead Console During PDI on the ESCALADE IQ/IQL

During the Pre-Delivery Inspection (PDI) of the 2025-2026 ESCALADE IQ/IQL, all interior protective coverings should be removed as covered on the PDI form, including on the front overhead console. (Fig. […]

May 22, 2025
Diagnostic Tips for Audio and Display Screen Concerns on IOK Radios

Diagnostic Tips for Audio and Display Screen Concerns on IOK Radios

There may be several display screen concerns and other conditions on the infotainment system (RPO IOK) of some 2022-2025 Silverado, Tahoe, Suburban, Sierra, Yukon, HUMMER EV; 2024-2025 Corvette, Silverado HD […]

May 13, 2025
Required Information for Restricted IOK Radios

Required Information for Restricted IOK Radios

The infotainment system (RPO IOK) on 2022-2025 Silverado, Tahoe, Suburban, Sierra, Yukon, HUMMER EV; 2024-2025 Corvette, Silverado HD and Sierra HD models is on restriction. (Fig. 3) If the radio […]

May 13, 2025
Power Doors OTA Update Released for 2025 Escalade

Power Doors OTA Update Released for 2025 Escalade

2025 Escalade, Escalade ESV and Escalade V-Series models built early in the model year offered a power-assist exterior door system (RPO APD with R6W) that has power-assisted door opening and […]

May 13, 2025
QR Code Scanning Helps Avoid Input Mistakes When Programming Modules

QR Code Scanning Helps Avoid Input Mistakes When Programming Modules

When replacing a valve body or transmission on a GM vehicle, it is essential to gather Mechanical Characterization & Virtual Matching (MCVM) data from the cloud. Due to manufacturing variations, […]

May 13, 2025
GM Service Know-How Emerging Issues

GM Service Know-How Emerging Issues

The monthly GM Service Know-How Emerging Issues seminars provide service/technical information on current issues and GM-certified repairs. This month the seminar previews the 2025 Corvette ZR1. (Fig. 12)   Fig. […]

May 13, 2025
New TAC Response Requested Process

New TAC Response Requested Process

A new GM Technical Assistance Center (TAC) process has been implemented to ensure the customer is being considered when TAC is working in partnership with dealership technicians to repair customers’ […]

May 9, 2025
Keep Your Cool — Air Conditioning Refrigerant Leak Diagnostic Tips

Keep Your Cool — Air Conditioning Refrigerant Leak Diagnostic Tips

All current GM vehicles are manufactured with fluorescent dye installed in the air conditioning refrigerant system. The dye mixes and flows with the A/C compressor oil to help in locating […]

April 30, 2025
Water Leak at the A-Pillar Body Plug

Water Leak at the A-Pillar Body Plug

There may be several inoperative electrical features on some 2019-2025 Blazers. (Fig. 4) These conditions may include inoperative door chimes and door lamps, inoperative power mirrors or a distorted driver-side […]

April 30, 2025
Unlatching the Front Compartment Hood with a Weak 12V Battery

Unlatching the Front Compartment Hood with a Weak 12V Battery

The front compartment hood on some 2024-2025 Corvette models may not fully unlatch when one of the hood release buttons is pressed if the 12V battery is weak, resulting in […]

April 30, 2025
Differences in Approach Lighting on Mid-Size SUVs

Differences in Approach Lighting on Mid-Size SUVs

The approach lighting on the 2024-2025 Traverse and Acadia has several differences compared to the lighting elements on the 2025 Enclave. It’s important to understand these differences when diagnosing any […]

April 30, 2025
April Service Newsletter from the Experts at GM TAC

April Service Newsletter from the Experts at GM TAC

The latest diagnostic assistance from the professionals at the GM Technical Assistance Center is now available in the April GM Technical Assistance Center (TAC) Newsletter. It covers a number of […]

April 30, 2025