B1974

B1974-POWER LIFTGATE CLOSE DIRECTION - RATCHET SECONDARY SWITCH PERFORMANCE





For a complete wiring diagram refer to Diagrams/Electrical

- When Monitored:

Whenever the power liftgate is performing a power closing operation.

- Set Condition:

The ratchet secondary switch was detected as open when the Power Liftgate Drive Unit Position Sensor count is greater than 40.





Diagnostic Test

1.DTC PRESENT

NOTE: This DTC will only set during the releasing operation after the four second time out. This may make it difficult to reproduce.

With the scan tool, record and erase DTC's.

Turn the ignition off, wait 10 seconds, then turn the ignition on.

Operate the power liftgate several times if possible.

With the scan tool, read ACTIVE DTCs.

Does the scan tool display B1974-POWER LIFTGATE CLOSE OPERATION - RATCHET SECONDARY SWITCH PERFORMANCE?

Yes

- Go To 2

No

- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors for an intermittent condition. Operate the door several times and check for any binding or other obstructions.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

2.BINDING LIFTGATE

Examine the liftgate for proper fit and alignment, loose/hard or torn seals, misaligned latch striker or anything that would cause an obstruction to proper operation.

Manually operate the liftgate of a known good vehicle and notice the effort needed to open and close.

Compare the effort needed on the disabled liftgate.

Especially notice the effort needed to unlatch and close the liftgate.

Does it take more effort to operate the liftgate than it should?

Yes

- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 3

3.POWER LIFTGATE MODULE

With the scan tool, monitor the SECONDARY RATCHET SWITCH CLOSED.

Using a screwdriver, click the latch to the first detent while observing the scan tool.

Unlatch the latch by pressing the handle switch and observe the scan tool for a change of state.

Repeat this step several times while moving the liftgate in different positions and wiggling the harness to check for an intermittent open or shorted circuit.

Did the scan tool show the switch state changing correctly every time?

No

- Go To4

Yes

- Replace the Power Liftgate Module.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

4.(Q901) LOGIC GROUND WIRE OPEN





Turn the ignition off.

Turn all lights off.

Disconnect the Power Liftgate Latch harness connector.

Measure the resistance between ground and the (Q901) Logic Ground circuit in the Liftgate Latch harness connector.

Wiggle the harness while observing the ohmmeter.

Is the resistance below 9.5 ohms?

Yes

- Go To5

No

- Repair the (Q901) Logic Ground wire for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

5.(Q76) LATCH SECONDARY POSITION SENSE WIRE OPEN





Disconnect the Power Liftgate Module C2 harness connector.

Measure the resistance of the (Q76) Latch Secondary Position Sense between the PLG Module C2 harness connector and the Liftgate Latch harness connector.

Wiggle the harness while observing the ohmmeter.

Is the resistance below 2.0 ohms?

No

- Repair the (Q76) Latch Secondary Position Sense circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

Yes

- Go To 6

6.(Q76) LATCH SECONDARY POSITION SENSE WIRE SHORT TO VOLTAGE





Turn the ignition on.

Measure the voltage between the (Q76) Latch Secondary Position Sense wire and ground in the Liftgate Latch harness connector.

Wiggle the harness while observing the voltmeter.

Is there any voltage present?

No

- Replace the Power Liftgate Latch.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

Yes

- Repair the (Q76) Latch Secondary Position Sense wire for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test