Hard to summarize my issues in an easy title. 2003 Trailblazer LT.
I've been having a few issues with my 4wd this winter. When it snows, I'll put it in 4hi to leave my neighborhood. I go back to 2hi when I'm on dry pavement (highways etc.). When I get off the highway, I often have to go back to 4hi because of unplowed roads. This is when I get a service 4wd light, but it will go into 4hi. It will switch back to 2hi, but the service 4wd light stays on. After I shut the truck off and turn it back on, the light is gone.
Yesterday, I switched to 4hi going up a hill near my house heading home. I got the service 4wd light and I kept slipping. It finally engaged and I got traction, only it seemed very sluggish. Turns out it went into 4lo with the switch on 4hi. The switch was physically on hi but light was over lo. Fortunately I only had about a block to drive in snow until my driveway. I tried putting it back in 2hi, but I didn't know it needed to be in neutral. I ended up leaving the switch on 2hi and putting it in park shutting it off and going in to research the issue. I went back out and turned my key to on, the truck lurched and 2hi lit up. This morning, I put it in 4hi, it went, and I left the driveway. It switched to 2hi when I got to dry pavement with no service light. I did have a prior instance where it was stuck in 4hi and I shut it off with it set to 2hi. Corrected itself when I turned it back on later.
Sorry, for the long story, but I can't find anything similar to my problem. I'm leaning toward encoder motor or tccm. I suppose it could be the switch as well. Just odd it went into 4lo without being commanded. When I was trying to switch it out, the flashing light followed the selector, so it would seem the contacts are ok. I didn't think it could go into 4lo without being in neutral either. I would also conclude the sector light is not tied to the switch position. It must be getting input from somewhere else. My thought is encoder motor is going out.
Any ideas guys? Thanks
I've been having a few issues with my 4wd this winter. When it snows, I'll put it in 4hi to leave my neighborhood. I go back to 2hi when I'm on dry pavement (highways etc.). When I get off the highway, I often have to go back to 4hi because of unplowed roads. This is when I get a service 4wd light, but it will go into 4hi. It will switch back to 2hi, but the service 4wd light stays on. After I shut the truck off and turn it back on, the light is gone.
Yesterday, I switched to 4hi going up a hill near my house heading home. I got the service 4wd light and I kept slipping. It finally engaged and I got traction, only it seemed very sluggish. Turns out it went into 4lo with the switch on 4hi. The switch was physically on hi but light was over lo. Fortunately I only had about a block to drive in snow until my driveway. I tried putting it back in 2hi, but I didn't know it needed to be in neutral. I ended up leaving the switch on 2hi and putting it in park shutting it off and going in to research the issue. I went back out and turned my key to on, the truck lurched and 2hi lit up. This morning, I put it in 4hi, it went, and I left the driveway. It switched to 2hi when I got to dry pavement with no service light. I did have a prior instance where it was stuck in 4hi and I shut it off with it set to 2hi. Corrected itself when I turned it back on later.
Sorry, for the long story, but I can't find anything similar to my problem. I'm leaning toward encoder motor or tccm. I suppose it could be the switch as well. Just odd it went into 4lo without being commanded. When I was trying to switch it out, the flashing light followed the selector, so it would seem the contacts are ok. I didn't think it could go into 4lo without being in neutral either. I would also conclude the sector light is not tied to the switch position. It must be getting input from somewhere else. My thought is encoder motor is going out.
Any ideas guys? Thanks
