Diagnostic Aids

When a shorted-to-ground condition exists in circuit 694 and the BCM has been requested to activate the driver door unlock relay, the BCM will attempt to switch circuit 694 to battery voltage. High current flow will result and the BCM output will go into a protective state. The BCM output will not allow itself to be activated for as much as 3 minutes. The fuse opens when block is activated.
Inspect the wiring harness for damage. Check for broken or chafed insulation.
If a fault is suspected to be intermittent, wiggling the harness wiring may help in locating the fault.

Fig 1: Left Front Door Only Unlock Circuit Chart 3

Courtesy of GENERAL MOTORS CORP.