how to troubleshoot GMC Sierra T1XX (2019-Present) electrical issues?

Learn how to troubleshoot electrical issues in GMC Sierra T1XX (2019-Present). Step-by-step guide with diagnostic steps and repair instructions.

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, socket set, torque wrench, wire brush, and electrical contact cleaner.
• Safety Warnings: Disconnect the battery before working on electrical systems to avoid short circuits.

2. Address Battery Issues

• Sub-steps:
  1. Disconnect the negative terminal followed by the positive terminal from the battery.
  2. Clean the battery terminals and cable connectors using a wire brush and electrical contact cleaner.
  3. Reconnect the battery, ensuring a secure fit.

3. Replace Blown Fuses

• Sub-steps:
  1. Identify the location of the fuse box using the owner’s manual.
  2. Remove the relevant fuse using a fuse puller or pliers.
  3. Replace with a new fuse of the same amperage rating.
  4. Test the electrical component for functionality after replacement.

4. Repair Ground Connections

• Sub-steps:
  1. Locate all ground points on the vehicle, focusing on the engine block and chassis.
  2. Remove the ground bolts and clean the contact surfaces with a wire brush.
  3. Reattach the ground connections and tighten to manufacturer specifications.

5. Test and Replace Components

• Sub-steps:
  1. For the alternator, measure the output voltage with the engine running; it should be between 13.5V and 14.5V.
  2. If out of range, replace the alternator.
  3. For the starter, check for voltage at the starter solenoid when the key is turned to the start position; if no voltage, replace the starter.