Diagnostic Aids

Check for spread connectors at pass-thru connector. Code 68 will set when going to default (2nd gear). If code is intermittent, see INTERMITTENTS in appropriate TESTS W/O CODES article in this section. See below.

• TESTS W/O CODES - GASOLINE
• TESTS W/O CODES - 6.5L DIESEL

Fig 1: Code 68 Schematic (4L80-E Diesel) Overdrive Ratio Error

Fig 2: Code 68 Schematic (4L80-E Gasoline) Overdrive Ratio Error

Fig 3: Code 68 Flow Chart Overdrive Ratio Error