New problem in my ‘96 K1500. Went to shift it into 4lo, no lights on the push-button actuator were lit. No biggie, right? Well, I put it in neutral and pressed 4lo, and I hear the case shift, then immediately shift back. Both 4hi and 4lo lights are now blinking, then after 3 seconds they stay solid on til I turn the truck off. Now that I’ve restarted the truck, the same thing is happening. It shifts onto 4lo (does the same for 4hi too), then shifts immediately back to 2wd, followed By blinking lights. I replaced the front axle engagement about 2 years ago with the upgraded electric motor version, and have had no problems shifting into either 4x4 range up to this point.