ON 668:
DTC 668 indicates an open in the TR circuit.
DTC 667 indicates a short to ground in the TR circuits.
Possible causes:
* Misadjusted linkage.
* Open or short in harness circuits.
* Damaged TR sensor.
* Damaged Powertrain Control Module (PCM) .
* Key "OFF".
* Apply parking brake.
* Place transmission in "NEUTRAL".
* Verify that Transmission Range Sensor Tool (Rotunda T91P-7010-AHT) or equivalent fits in the appropriate slot.
* Does the tool fit properly?
Yes -- Remove tool. Go to TD2. See: TD2 - Check Continuity of Transmission Range Sensor Harness
No -- Place the transmission in "NEUTRAL". Loosen the two TR sensor mounting bolts. Move the sensor to allow insertion of the Transmission Range Sensor Tool in the appropriate slots. Tighten the two mounting bolts to specification. Remove tool. Verify shift linkage adjustment. Clear continuous memory. See: Quick Test (Extracting and Clearing Codes)\Clearing Codes
Checking on the other....
