Note On Intermittents

Manipulate related ECM and BCM wiring in each gear range while looking for a change in BD41 or ED74 display values to check for intermittent open or short to ground. Also check terminals for good contact at ECM, BCM and PRNDD21 switch. If good contact exists and Code B127 continues to set, replace PRNDD21 switch.

Fig 1: Code B127: Circuit Diagram

Fig 2: Code B127: Flow Chart Gear Selector Switch Circuit (1 of 3)

Fig 3: Code B127: Flow Chart Gear Selector Switch Circuit (2 of 3)

Fig 4: Code B127: Flow Chart Gear Selector Switch Circuit (3 of 3)