Circuit/System Testing

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.

Ignition/Vehicle - Off
Disconnect the electrical connector:
- B14E Transmission Input/Intermediate Shaft Speed Sensor
- X1@T12 Automatic Transmission Assembly
Ignition - On/Vehicle - In Service Mode
Test for 8.6 to 9.2 V between the test points: 9 V Reference circuit terminal 1 X1@T12 Automatic Transmission Assembly (harness side) & Ground
- If less than 8.6 V
1. Disconnect the electrical connector: K71 Transmission Control Module
2. Test for infinite resistance between the test points: 9 V Reference circuit terminal 1 X1@T12 Automatic Transmission Assembly (harness side) & Ground
  - If less than infinite resistance - Repair the short to ground on the circuit.
  - Go to next step: If infinite resistance
3. Test for less than 2 ohms between the test points: 9 V Reference circuit terminal 1 X1@T12 Automatic Transmission Assembly (harness side) & Terminal 7@Control module harness
  - If 2 ohms or greater - Repair the open/high resistance in the circuit.
  - If less than 2 ohms - Replace the component: K71 Transmission Control Module
- If greater than 9.2 V
1. Ignition/Vehicle - Off
2. Disconnect the electrical connector: K71 Transmission Control Module
3. Ignition - On/Vehicle - In Service Mode
4. Test for less than 1 V between the test points: 9 V Reference circuit terminal 1 X1@T12 Automatic Transmission Assembly (harness side) & Ground
  - If 1 V or greater - Repair the short to voltage on the circuit.
  - If less than 1 V - Replace the component: K71 Transmission Control Module
- Go to next step: If between 8.6 and 9.2 V
Verify the scan tool parameter:
- {P17F5, P17F6, P17F7} Transmission Park Valve Position Sensor 1 = Less than 0.4 V
- {P17FA, P17FB, P17FC} Transmission Park Valve Position Sensor 2 = Less than 0.4 V
- If 0.4 V or greater
1. Ignition/Vehicle - Off
2. Disconnect the electrical connector: K71 Transmission Control Module
3. Ignition - On/Vehicle - In Service Mode
4. Test for less than 0.4 V between the test points:
  - {P17F5, P17F6, P17F7} Signal circuit terminal 17 X1@T12 Automatic Transmission Assembly (harness side) & Ground
  - {P17FA, P17FB, P17FC} Signal circuit terminal 16 X1@T12 Automatic Transmission Assembly (harness side) & Ground
  - If 0.4 V or greater - Repair the short to voltage on the circuit.
  - If less than 0.4 V - Replace the component: K71 Transmission Control Module
- Go to next step: If less than 0.4 V
Connect a 3 A fused jumper wire between the test points:
- {P17F5, P17F6, P17F7} Signal circuit terminal 17 X1@T12 Automatic Transmission Assembly & 9 V Reference circuit terminal 1 X1
- {P17FA, P17FB, P17FC} Signal circuit terminal 16 X1@T12 Automatic Transmission Assembly & 9 V Reference circuit terminal 1 X1
Verify the scan tool parameter:
- {P17F5, P17F6, P17F7} Transmission Park Valve Position Sensor 1 = Greater than 4.8 V
- {P17FA, P17FB, P17FC} Transmission Park Valve Position Sensor 2 = Greater than 4.8 V
- If less than 4.8 V
1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
2. Disconnect the electrical connector: K71 Transmission Control Module
3. Test for infinite resistance between the test points:
  - {P17F5, P17F6, P17F7} Signal circuit terminal 17 X1@Component harness & Ground
  - {P17FA, P17FB, P17FC} Signal circuit terminal 16 X1@Component harness & Ground
  - If less than infinite resistance - Repair the short to ground on the circuit.
  - Go to next step: If infinite resistance
4. Test for less than 2 ohms between the test points:
  - {P17F5, P17F6, P17F7} Signal circuit terminal 17 X1@Component harness & Terminal 61@Control module harness
  - {P17FA, P17FB, P17FC} Signal circuit terminal 16 X1@Component harness & Terminal 59@Control module harness
  - If 2 ohms or greater - Repair the open/high resistance in the circuit.
  - If less than 2 ohms - Replace the component: K71 Transmission Control Module
- Go to next step: If greater than 4.8 V
Ignition/Vehicle - Off & Remove - Jumper wire(s)
Remove the component: Control Valve Body Cover
Connect the electrical connector: X1@T12 Automatic Transmission Assembly
Disconnect the electrical connector: B316 Transmission Park Valve Position Switch
Ignition - On/Vehicle - In Service Mode
Verify the scan tool parameter:
- {P17F5, P17F6, P17F7} Transmission Park Valve Position Sensor 1 = Less than 0.4 V
- {P17FA, P17FB, P17FC} Transmission Park Valve Position Sensor 2 = Less than 0.4 V
- If 0.4 V or greater
  Replace the component: Automatic Transmission Wiring Harness
Test for 8.6 to 9.2 V between the test points: 9 V Reference circuit terminal 1 & Ground
- If not between 8.6 and 9.2 V
  Replace the component: Automatic Transmission Wiring Harness
- Go to next step: If between 8.6 and 9.2 V
Connect a 3 A fused jumper wire between the test points:
- {P17F5, P17F6, P17F7} Signal circuit terminal 2@B316 Transmission Park Valve Position Switch (harness side) & Terminal 1
- {P17FA, P17FB, P17FC} Signal circuit terminal 3@Component harness & Terminal 1
Verify the scan tool parameter:
- {P17F5, P17F6, P17F7} Transmission Park Valve Position Sensor 1 = Greater than 4.8 V
- {P17FA, P17FB, P17FC} Transmission Park Valve Position Sensor 2 = Greater than 4.8 V
- If less than 4.8 V
  Replace the component: Automatic Transmission Wiring Harness
- Go to next step: If 4.8 V or greater
Test or replace the component: B316 Transmission Park Valve Position Switch