P099C Possible Causes
Faulty shift solenoid “G”
Shift solenoid “G” harness is open or shorted
Poor electrical connection in shift solenoid G circuit
What Does It Mean?
First Diagnose Code P099C
Check the “possible causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
P099C
Possible Symptoms
Check Engine Light illuminated (or Service Engine Soon warning light)
P099C Description
The Transmission Control Module (TCM) monitors the shift solenoid signal. The TCM sets the OBDII code when the shift solenoid does not meet factory specifications.