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Chevrolet Silverado 2007-2013: Why is My 4WD Selector Light On?

Read more to learn how to troubleshoot your Chevrolet Silverado 1500's 4WD selector light.

By Charlie Gaston - June 2, 2015

This article applies to the Chevrolet Silverado 1500 (2007-2013).

If the 4WD selector light in your truck won't work properly, the problem could be any number of things. However, don't anticipate making a drive down to your local Chevrolet dealer or mechanic for help just yet. Using just a few handy troubleshooting tips and inexpensive materials, you can usually diagnose and repair a faulty 4WD selector light in about 15 minutes to an hour. Here are a few simple things you can do to get this light working properly again.

Materials Needed

  • On-board diagnostic tool
  • Heavy weight gear oil
  • Transfer fluid oil
  • 4WD sensor replacement

Step 1 – Check the fluid in the transfer case

It might be too low or bad.

Lubrication is especially important if you won't be switching your Silverado 1500 into 4DW on a regular basis. To avoid having your 4WD selector light come on and go off at random, it's recommended that you switch your vehicle into 4WD at least once a month and properly maintain your transfer case fluid.

  • When the engine is cool, remove the drain and fill plug at the bottom of your transfer case, which should be facing your rear axle.
  • Replace the old transfer case oil, as needed, using a premium grade transfer case oil.
  • It's recommended that you also check the fluid in your front differential.
  • Use a premium-quality, heavy-weight gear oil from your local auto parts store.
Figure 1. There are a number of transfer case oils on the market.

Step 2 – Replace the 4WD selector switch on the dashboard

It might be faulty.

  • This is an easy DIY repair that costs just $55 to $60 for parts.
  • This easy-to-use plug and play replacement requires less than 15 minutes.
  • If your truck is still under warranty, you can set up a service appointment to have your dealer complete the repair at no cost to you.
Figure 2. This is a sample replacement.

Step 3 – Check the codes

There might be an electrical problem, or your fuse has blown.

Using an on-board diagnostics tool, check your vehicle's trouble codes. However, generally speaking, the usual culprits are a faulty 4WD sensor, low or bad transfer case fluid or part failure due to infrequent use.

  • Checking your codes is also important if you've been lax in following your 4WD system maintenance schedule.
  • If there is an electrical problem, it's recommended that you seek the help of licensed automotive professional.
  • Your mechanic or dealer will check your vehicle's wiring and 4WD system as well as perform other diagnostics.
  • It's worth noting that the problem could be a faulty actuator in your transfer case, which should be covered under your warranty.

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