B1277 · メーカー技術情報

FORD, LINCOLN · 2021-12-14

Some 20182021 Expedition/Navigator vehicles may exhibit inoperative reverse lamps with DTC B1277 stored in the body control module (BCM). The vehicle may also exhibit the auto dimming rear view mirror becoming dark as soon as the key is turned on or is inoperative. This may be due to incorrect wiring of an aftermarket 5 pin jumper connector from a non-Ford windshield supplier that is causing a short to ground. To correct this condition, inspect if the windshield was recently replaced and verify the circuits in the 5 pin jumper connector located between connector C9440 and C9224 are routed in the correct pin location and adjust as necessary. Refer to the Wiring Diagram, Cell 124-10.

CADILLAC, CHEVROLET, GMC · 2015-05-01

This Preliminary Information communication provides information to the technician on the steps to diagnose and repair vehicles that may have a buffeting vibration and/or drone type noise, exhaust tone change, and/or body pressure booming. The concern may be most noticeable while the engine is operating in 4-cylinder Active Fuel Management mode in the 1,100-1,400 RPM range. If the noise is excessive it may excite the roof sheet metal and compound the issue, if this concern is found refer to the latest version of PIT5318. If the concern is qualified to be present during V4 mode operation, but is deemed to be normal by comparing to a like vehicle, then no further repairs should be made, as this is a normal characteristic. If the concern is qualified to be present during V4 mode operation,…