P0861 Possible Causes
Faulty Shift Control Module “A”
Shift Control Module “A” harness is open or shorted
Poor electrical connection in Shift Control Module A circuit
What Does It Mean?
First diagnose the P0861 code
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.
P0861 Possible Symptoms
Check Engine Light illuminated (or Service Engine Soon warning light)
P0861 Description
The Engine Control Module (ECM) monitors the Shift Control Module. The ECM sets the OBDII code when there is a communication problem with the Shift Control Module.