1999 Chevy Silverado Converter Not Locking

ndevin25 · December 4, 2018

I have a 1999 ext. cab short bed Chevy Silverado 1500 z71 4x4 with the 5.3 and 4l60e. Truck has 200k on it. I recently bought it and it drove home fine no problems. The next day the transmission lost three and four so I had my guy rebuild me one and I went and swapped him my core and swapped trannys. I put everything back together, top it off with fluid and it shifts great. Only problem is the torque converter is not locking up. Scanned the truck and I have codes c0281 , p1870 , and p0332. I already replaced the brake light switch with no luck, it didn’t change anything. What should I be looking at next? The orange wire at the switch is getting power like it should. I believe when I tested it with my meter that all of the wires had power when pedal was not depressed. Any help would be apprected. Thank you

riverbanks · December 4, 2018

Years ago I had p0332,kept it out of lockup, but I didn't have p1870, knock sensor harness is at bellhousing or close to anyway,any harm done to it?and did you wash motor? just thinking of common problems

riverbanks · December 4, 2018

Co281,loss of 12v to ecbm?does cruise work?third brake light working? just going down the list of possibilities

ndevin25 · December 5, 2018

Cruise works perfectly, third brake light works (At least one bulb does). I can check the knock sensor harness but my Camaro and all of the other Chevy trucks that I have had has had that code with no transmission issues. I never washed the motor I pulled the tranny out, put a new rear main in, and then reinstalled the rest. How do I check voltage at the EBCM? Is there a way I can test the brake switch? Or test some wires on the tranny?