Four wheel drive will not stay engaged after replacing the encoder motor

1997 CHEVROLET SILVERADO
260,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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11997Z71
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  • 2 POSTS
i changed the encoder motor it worked fine for two days, now the four wheel drive will engage but in a minute or two the the TCCM will click a few times and the indicator lights will flash back and forth then go into 2hi. i can put it back into 4hi and it will work for a bit longer before wigging out again. after a few times of this the TCCM will give up and leave it in 2hi and the push buttons do not work until i pull the tcase fuse and reset the TCCM.
Dec 12, 2016 at 7:23 AM
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HMAC300
  • CERTIFIED EXPERT
  • 48,601 POSTS
scan for codes and check ground leading to encoder motor may be bad. also, when you connect connector put dielectric grease there for better contact.
Dec 12, 2016 at 7:47 AM
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11997Z71
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  • 2 POSTS
codes are number one and number two sometimes just number two. I put dielectric grease on all connections and tested voltage and ground at encoder motor. just for fun i have tried a different tccm and dash switch achieving no change in the problem.
Dec 12, 2016 at 2:17 PM
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HMAC300
  • CERTIFIED EXPERT
  • 48,601 POSTS
there is no code one or two. it is probably twelve so it means it is working okay. check harness and have a mechanic check it. This may be an internal problem if not staying in gear.
Dec 12, 2016 at 3:16 PM