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How to Troubleshoot the Electrical System in a Chevy Avalanche

by Contributor

The electrical system of this full size crew-cab pick up truck runs about average. It's not the worst, but it's not the best either. Expect problem unless you have a 2006 Chevy Avalanche. This was the best year the Avalanche electrical system had in recent years. Otherwise, be prepared to do some troubleshooting and repairs on your truck. The key to keeping the electrical system moving smoothly is maintenance.

Step 1

Keep rust and corrosion on cables and connections to a minimum because many electrical problems start here. Maintain wiring and connections by keeping them clean. It could make the difference in how often you visit the dealer.

Step 2

Replace your battery with one that has the same or better CCA (cold cranking amps) rating when you need a battery replacement. The Avalanche's energy needs are based on a specific CCA rating. If you've added things, a better CCA rating can only help your electrical system. Make sure that any battery you buy fits in the tray and with the cable connections of your truck.

Step 3

Maintain your starter for a longer life. As the largest power user of all your components, you can make your starter last longer if you get in the habit of starting your truck with electrical system items like the stereo and air conditioning turned off. If it takes awhile to get your Avalanche up and going, it could be a sign of age. If your truck isn't that old, look for a bad electrical connection to the battery or a failure at a relay or fusible link.

Step 4

Check the batteries in your remotes if they suddenly quit working. If batteries work and you drive a 2003 Avalanche, you're not alone with having a problem. Another problem that some owners have experienced is with electrical items not working on one of the doors. Always check fuses and relays first. If they check out, you may be looking at a short or a poor ground.

Step 5

Find a TSB for Passenger Door Module if you're having trouble with the passenger door of a 2003 Avalanche. Alert your dealer with the information, because the module requires reprogramming or replacement when components fail in the door.

Figure out what's wrong with nonworking door locks by checking the relay switch first. If there's no click, check for voltage at the door switch. No voltage means that you need to check the wiring between the fuse panel and switch for a break or short. If you do have voltage, but no click, you need to test the switch for continuity. If you haven't find the problem, check between the switch and relay and then at the solenoid. If you make it to the solenoid and have voltage, you need to replace the solenoid.

Items you will need

  • Digital volt-ohmmeter
  • Spare fuses for Avalanche

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