Blue ALDL wire connected to ground

[S.hafsmo]

I've just discovered that someone has installed some sort of jumper between the blue wire on the ALDL connector and ground. Anyone care to guess what half-assed repair has been attempted? No fault codes appear when the jumper is removed.

The blue wire acc. to FSM,

SUPPLEMENTAL INFLATABLE RESTRAINT
(SIR)~ SERIAL DATA RECEIVE DIAGNOSTIC
ENABLE

Is it an attempted bypass on a poorly grounded sensor?