18/07/2026 6:12 am
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Automotive Q&A
BCM stays awake because a liftgate-ajar input flickers after locking
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A 2017 Traverse has a 180 mA overnight draw. The BCM never completes its normal sleep sequence, and recorded data shows the liftgate-ajar input changing state for a fraction of a second even though the gate is closed and the dash warning does not remain on. Pressing the gate inward makes the input stable.
Would you adjust the striker first, or test the latch switch and wiring under load?
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19/07/2026 6:25 am
Document latch alignment and mechanical preload, but test the switch circuit before changing geometry. Monitor the input while backprobing the latch signal, reference and ground; compare a manual latch closure with the installed gate. If the signal changes electrically at the latch while supply and ground remain stable, the internal switch is failing. If the latch stays stable but BCM data changes, inspect the harness and module input.
Make sure the latch is released before closing the gate after a bench test. The sleep-current retest should run long enough to include the original wake interval.
Topic starter
20/07/2026 8:37 am
The signal changed directly at the latch with no movement in supply or ground. A worn internal microswitch was the cause; striker alignment was already correct. After latch replacement, the BCM slept normally and current remained between 21 and 25 mA overnight.