Circuit/System Testing
WARNING: This page is about a different car, the 2019 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition/Vehicle & All vehicle systems - Off
- Disconnect the electrical connector:X1 @ T12 Automatic Transmission Assembly
- Test for less than 10 ohms between the test points:Low Reference circuit terminal 16 @ Component harness & Ground
- If 10 ohms or greater
- Disconnect the electrical connector:K20 Engine Control Module
- Test for less than 2 ohms between the test points:Low Reference circuit terminal 16 @ Component harness & The other end of the circuit @ Control module harness
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Replace the component:K20 Engine Control Module
- Go to next step: If less than 10 ohms
- Ignition - On / Vehicle - In Service Mode
- Test for 4.8 to 5.2 V between the test points:5 V Reference circuit terminal 7 & Ground
- If less than 4.8 V
- Ignition/Vehicle - Off
- Disconnect the electrical connector:K20 Engine Control Module
- Test for infinite resistance between the test points:5 V Reference circuit terminal 7 @ Component harness & Ground
- If less than infinite resistance - Repair the short to ground on the circuit.
- Go to next step: If infinite resistance
- Test for less than 2 ohms between the test points:5 V Reference circuit terminal 7 @ Component harness & The other end of the circuit @ Control module harness
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Replace the component: K20 Engine Control Module
- If greater than 5.2 V
- Ignition/Vehicle - Off
- Disconnect the electrical connector:K20 Engine Control Module
- Ignition - On / Vehicle - In Service Mode
- Test for less than 1 V between the test points:5 V Reference circuit terminal 7 @ Component harness & Ground
- If 1 V or greater - Repair the short to voltage on the circuit.
- If less than 1 V - Replace the component:K20 Engine Control Module
- Go to next step: If between 4.8 and 5.2 V
- Ignition/Vehicle - Off
- Install & Setup - EL-38522 Variable Signal Generator
- Voltage - 5 V
- Frequency - 120 Hz
- Duty Cycle - 50%
- Black lead @ Ground
- Red lead @
- { P0707, P0708 } Signal circuit terminal 17
- { P2802, P2803 } Signal circuit terminal 19
- Ignition - On / Vehicle - In Service Mode
- Verify the scan tool parameter:
- { P0707, P0708 } Transmission Range Sensor 1 = 48 to 52%
- { P2802, P2803 } Transmission Range Sensor 2 = 48 to 52%
- If not in the specified range
- Ignition/Vehicle - Off
- Disconnect the electrical connector:
- { P0707, P0708 } K71 Transmission Control Module
- { P2802, P2803 } K20 Engine Control Module
- Ignition - On / Vehicle - In Service Mode
- Test for less than 1 V between the test points:
- { P0707, P0708 } Signal circuit terminal 17 @ Component harness & Ground
- { P2802, P2803 } Signal circuit terminal 19 @ Component harness & Ground
- If 1 V or greater - Repair the short to voltage on the circuit.
- Go to next step: If less than 1 V
- Ignition/Vehicle - Off
- Test for infinite resistance between the test points:
- { P0707, P0708 } Signal circuit terminal 17 @ Component harness & Ground
- { P2802, P2803 } Signal circuit terminal 19 @ Component harness & Ground
- If less than infinite resistance - Repair the short to ground on the circuit.
- Go to next step: If infinite resistance
- Test for less than 2 ohms between the test points:
- { P0707, P0708 } Signal circuit terminal 17 @ Component harness & The other end of the circuit @ Control module harness
- { P2802, P2803 } Signal circuit terminal 19 @ Component harness & The other end of the circuit @ Control module harness
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Replace the component:
- { P0707, P0708 } K71 Transmission Control Module
- { P2802, P2803 } K20 Engine Control Module
- Go to next step: If in the specified range
- Connect the electrical connector:X1 @ T12 Automatic Transmission Assembly
- Ignition/Vehicle - Off
- Remove the component:Automatic Transmission Fluid Pan
- Connect the electrical connector:X1 @ T12 Automatic Transmission Assembly
- Disconnect the electrical connector:B303 Transmission Range Sensor
- Install & Setup - EL-38522 Variable Signal Generator
- Voltage - 5 V
- Frequency - 120 Hz
- Duty Cycle - 50%
- Black lead @ Ground
- Red lead @
- { P0707, P0708 } Signal circuit terminal 2
- { P2802, P2803 } Signal circuit terminal 3
- Ignition - On / Vehicle - In Service Mode
- Verify the scan tool parameter:
- { P0707, P0708 } Transmission Range Sensor 1 = 48 to 52%
- { P2802, P2803 } Transmission Range Sensor 2 = 48 to 52%
- If not in the specified range
Replace the component:Automatic Transmission Wiring Harness
- Go to next step: If in the specified range
- Test or replace the component:B303 Transmission Range Sensor
NOTE:
It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.