Diagnostic Fault Information

WARNING: This page is about a different car, the 2023 GMC Acadia. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

The components are listed from the least to the most intrusive to service.

Component	DTC	Condition
M123 Transmission Park Valve Lock Solenoid Actuator	P18A8	Binding, sticking or stuck component: Valve Debris on the component. Damaged component: Valve or Bore - Scored Spring
Control Valve Body Mode 2 Electronic Transmission Range Selector Valve Electronic Transmission Range Selector Mode Enable Valve/Spring Control Valve Body Spacer Plate Feed Limit Valve/Spring Clutch Selector Valve/Spring	P18A8	Binding, sticking or stuck component: Valve Debris on the component. Damaged component: Valve or Bore - Scored Spring
Control Solenoid Valve Body Mode 1 Electronic Transmission Range Selector Valve	P18A8	Binding, sticking or stuck component: Valve Debris on the component. Damaged component: Valve or Bore - Scored Spring

Component

DTC

Condition

M123 Transmission Park Valve Lock Solenoid Actuator

P18A8

Binding, sticking or stuck component: Valve
Debris on the component.
Damaged component:
- Valve or Bore - Scored
- Spring

Control Valve Body

Mode 2 Electronic Transmission Range Selector Valve
Electronic Transmission Range Selector Mode Enable Valve/Spring
Control Valve Body Spacer Plate
Feed Limit Valve/Spring
Clutch Selector Valve/Spring

P18A8

Binding, sticking or stuck component: Valve
Debris on the component.
Damaged component:
- Valve or Bore - Scored
- Spring

Control Solenoid Valve Body

Mode 1 Electronic Transmission Range Selector Valve

P18A8

Binding, sticking or stuck component: Valve
Debris on the component.
Damaged component:
- Valve or Bore - Scored
- Spring