B1942
B1942-POWER LIFTGATE POSITION SENSOR 2 CIRCUIT PERFORMANCE
Theory of Operation
The Power Liftgate Position Sensor is located inside the Power Drive Unit. It provides two signals which informs the module of the true position of the liftgate. These signals (Sensors 1 and 2) can be read on the scan tool and are displayed as True and False. The sensors are supplied 5 volts from the Power Liftgate Module. As the liftgate is in motion, the sensors will toggle between 5.0 volts and 0.02 volts.
- When Monitored:
Whenever the Power Liftgate is power opening or closing.
- Set Condition:
When the Power Liftgate Module senses the (Q205) Position Sensor Signal 2 circuit not pulsing during motor operation, this code will set.
1. DTC PRESENT
1. With the scan tool, record the DTCs.
2. Erase the DTCs.
3. Turn the ignition off, wait 10 seconds, then turn the ignition on.
4. If possible, operate the liftgate several times.
5. With the scan tool, read the Active DTCs.
Does the scan tool display B1942-POWER LIFTGATE POSITION SENSOR 2 CIRCUIT PERFORMANCE as active?
Yes
- Go To 2
No
- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
2. (Q901) LOGIC GROUND OPEN
1. Turn the ignition off.
2. Disconnect the Power Liftgate Drive Unit harness connector.
3. Disconnect the Power Liftgate Module C2 harness connector.
4. Measure the resistance of both of the (Q901) Logic Ground circuits between the Power Liftgate Drive Unit harness connector and the Power Liftgate Module C2 harness connector.
Is the resistance below 2.0 Ohms?
Yes
- Go To 3
No
- Repair the open in the (Q901) Logic Ground circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
3. (Q205) POSITION SENSOR SIGNAL 2 CIRCUIT SHORTED TO GROUND
1. Disconnect the Power Liftgate Module C1 harness connector.
2. Measure the resistance between ground and the (Q205) Position Sensor Signal 2 circuit
Is the resistance below 10,000 Ohms?
Yes
- Repair the short to ground in the (Q205) Position Sensor Signal 2 circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Go To 4
4. (Q205) POSITION SENSOR SIGNAL 2 CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition on.
2. Measure the voltage between ground and the (Q205) Position Sensor Signal 2 circuit
Is there any voltage present?
Yes
- Repair the short to voltage in the (204) Position Sensor Signal 2 circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Go To 5
5. (Q205) POSITION SENSOR SIGNAL 2 CIRCUIT OPEN
1. Turn the ignition off.
2. Measure the resistance of the (Q205) Position Sensor Signal 2 circuit between the PLG C1 connector and the Drive Unit connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 6
No
- Repair the open in the (Q205) Position Sensor Signal 2 circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
6. (Q203) POSITION SENSOR SUPPLY CIRCUIT OPEN
1. Measure the resistance of the (Q203) Position Sensor Supply circuit between the Power Liftgate Module C1 harness connector and the Power Liftgate Drive Unit harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 7
No
- Repair the open in the (Q203) Position Sensor Supply circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
7. (Q203) POSITION SENSOR SUPPLY CIRCUIT SHORTED TO GROUND
1. Measure the resistance between ground and the (Q203) Position Sensor Supply circuit.
Is the resistance below 10,000 Ohms?
Yes
- Repair the short to ground in the (Q203) Position Sensor Supply circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Go To 8
8. (Q205) POSITION SENSOR SIGNAL 2 CIRCUIT SHORTED TO THE (Q204) POSITION SENSOR SIGNAL 1 CIRCUIT
1. Measure the resistance between the (Q205) Position Sensor Signal 2 circuit and the (Q204) Position Sensor Signal 1 circuit
Is the resistance below 10,000 Ohms?
Yes
- Repair the short between the (Q205) Position Sensor Signal 2 circuit and the (Q204) Position Sensor Signal 1 circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Go To 9
9. POWER LIFTGATE MODULE
1. Reconnect the Power Liftgate Module C1 harness connector.
2. Reconnect the Power Liftgate Module C2 harness connector.
3. Reconnect the Power Liftgate Drive Unit harness connector.
4. Turn the ignition on.
5. While back probing, measure the voltage between ground and the (Q203) Position Sensor Supply circuit in the Power Liftgate Drive Unit harness connector.
NOTE: The graphic shows the terminal end of the connector for reference only. Back probe the wire end of the connector
Is the voltage approximately 4.8 volts?
Yes
- Go To 10
No
- Replace the Power Liftgate Module. Power Liftgate Control Module - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
10. POWER LIFTGATE DRIVE UNIT
1. Be sure the liftgate is in the full open position.
2. While back probing, measure the voltage between ground and the (Q205) Position Sensor Signal 2 circuit in the Power Liftgate Drive Unit harness connector.
NOTE: The graphic shows the terminal end of the connector for reference only. Back probe the wire end of the connector
3. While observing the voltmeter, manually lower the liftgate in short steps, waiting about one second between steps. Do this for about 12 steps.
Does the voltage toggle from approximately 4.8 volts to approximately 0.02 volts?
Yes
- Replace the Power Liftgate Module. Power Liftgate Control Module - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Replace the Power Liftgate Drive Unit. Power Liftgate Drive Unit - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.