Jim Grant's Tech Tips

'97 Chevy Tahoe, Resetting "Service Engine Soon" Light

Q: How do you clear or reset the Service Engine Soon Light on a ’97 Chevy Tahoe?

- Charles C.

A: There are three ways to clear or reset the Service Engine Soon light in your vehicle as well as most others. 1; with a computer scan tool. The software in the scan tool allows for turning the Service Engine Soon light off. While you’re having that performed, have the technician record the code/reason for the warning light being on, there may be a system problem that needs to be addressed. 2; disconnect the battery. Disconnecting the battery causes the computer to lose all its memory. The only problem there is you will not know why the warning light was on. 3; drive the vehicle. The warning light comes on if there is a system problem or if the key was in the on position and a computer sensor was disconnected. Just about every time you start the engine and drive your vehicle, the computer runs a series of system tests, this is called a drive cycle. Before the computer will turn off the warning light the vehicle and computer have to go through 3 drive cycles. If the computer has determined that there is not a system problem after 3 drive cycles of testing the light will be turned off. After about 50 drive cycles the computer will remove/delete the code that it stored. If after 3 or 4 days of driving the service engine soon light has not turned off then you may very well have a problem that needs to be addressed.