How do you reset ECM On a 1997 Chev Tahoe?

To reset the ECM (Engine Control Module) on a 1997 Chevy Tahoe, disconnect the negative battery cable and let it sit for about 10-15 minutes. This allows the stored memory to clear. Afterward, reconnect the negative cable, start the vehicle, and allow it to idle for a few minutes to let the ECM recalibrate. If needed, you can also use an OBD-II scanner to clear any trouble codes.