lemon-mirror:
Home >> GMC >> 1994 >> C3500 HD 6.5 F, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - Electronic Transmission >> Trouble Code Charts >> Code 68, Overdrive Ratio Error >> Notes

Code 68, Overdrive Ratio Error: Notes

The PCM/TCM monitors the difference in engine RPM and input shaft RPM. With transmission in Drive, scan tester reading should show engine speed closely matching input speed.

NOTE: Test numbers refer to numbers on diagnostic chart.
  1. Checks the indicated range signal to the selected range. A faulty switch could set this code.
  2. Checks TCC for slippage while in a commanded lock-up state.
· About lemon-mirror