2000 Volvo 770
Eaton 10 speed autoshift
Over the past 3,000 mile trip, on 4 occasions my truck wouldn't shift from 5th to 6th. Service light on shift tower was flashing. If I read code right, it was 43.
This fault code can be caused by failure of short to battery, short to ground, or open circuit is detected in a Range Solenoid Valve or Transmission Harness.
It will shift fine up to 5th, and when it does go to 6th, it will go to 10th gear with no issues.
Just the jump from 5th to 6th seems to be the issue.
Any ideas on how to know for sure what the issue it?
My shop couldn't get the diagnostic computer to sync up to truck 100%. It would get to 93% then time out.
Trans fluid is full.