P0888 GMC Transmission Relay Always Off
Possible causes
– Transmission Control Relay harness is open or shorted
– Transmission Control Relay circuit poor electrical connection
– Faulty Transmission Control Relay
– Faulty Transmission Solenoid/Pressure Switch Assembly
– Transmission Control Relay circuit poor electrical connection
– Faulty Transmission Control Relay
– Faulty Transmission Solenoid/Pressure Switch Assembly
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P0888 GMC Description
The Transmission Control Module (TCM) has detected less than 3 volts at the Transmission Control Relay output circuit
GMC Vehicle:GMC Acadia,GMC Canyon,GMC Envoy,GMC Savana 1500,GMC Savana 2500,GMC Savana 3500,GMC Sierra 1500,GMC Sierra 2500 HD,GMC Sierra 3500 HD,GMC Terrain,GMC Yukon,GMC Yukon XL 1500,GMC Yukon XL 2500,