B1891

B1891 - Power Liftgate Control Circuit 2 Low






For a complete wiring diagram, refer to.

• When Monitored: Whenever the power liftgate is power opening or power closing.

• Set Condition: When the power liftgate module senses voltage less than 1.5 volts on the liftgate close driver circuit, prior to starting a power cycle, this code will set.






Test Step 1 - DTC Present

• With the scan tool, record DTCs.

• Erase DTCs.

• Turn the ignition OFF, wait 10 seconds, then turn the ignition ON.

• If possible, operate the liftgate several times.

• With the scan tool, check for DTCs.

Does the scan tool display B1889 - Power Liftgate Control Circuit 2 Low?

Yes

• Go to Test Step 2

No

• Using the wiring diagram/schematic as a guide, inspect the wiring and connectors for an intermittent condition.

• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Test Step 2 - Liftgate Open Driver Circuit Short to Ground






• Turn the ignition OFF.

• Disconnect the power liftgate module C1 harness connector.

• Measure the resistance between ground and the liftgate open driver circuit.

Is the resistance less than 10k ohms?

Yes

• Go to Test Step 3

No

• Go to Test Step 4

Test Step 3 - Liftgate Open Driver Wire Short to Ground






• Disconnect the power liftgate drive unit connector.

• Measure the resistance between ground and the liftgate open driver circuit.

Is the resistance less than 10k ohms?

Yes

• Repair the liftgate open driver circuit for a short to ground.

• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

• Replace the power liftgate drive unit.

• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Test Step 4 - Check the Liftgate Close Driver for a Short to Ground






• Measure the resistance between ground and the liftgate close driver circuit in the power liftgate module C1 connector.

Is the resistance less than 10k ohms?

No

• Go to Test Step 6

Yes

• Go to Test Step 5

Test Step 5 - Check the Liftgate Close Driver Wire for a Short to Ground






• Disconnect the power liftgate drive unit connector.

• Measure the resistance between ground and the liftgate close driver circuit in the power liftgate module C1 connector.

Is the resistance less than 10k ohms?

No

• Replace the power liftgate drive unit.

• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Yes

• Repair the liftgate close driver circuit for a short to ground.

• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Test Step 6 - Liftgate Open Driver Circuit Short to Liftgate Close Driver Circuit






• Measure the resistance between the liftgate open driver circuit and the liftgate close driver circuit.

Is the resistance less than 1.0 ohms (should be approximately 4.3 ohms) ?

No

• Replace the power liftgate module.

• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Yes

• Go to Test Step 7

Test Step 7 - Liftgate Open Driver Wire Short to the Liftgate Close Driver Wire






• Disconnect the power liftgate drive unit harness connector.

• Measure the resistance between the liftgate open driver circuit and the liftgate close driver circuit.

Is the resistance less than 10k ohms?

No

• Replace the power liftgate drive unit.

• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Yes

• Repair the liftgate open driver circuit for a short to the liftgate close driver circuit.

• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior