P1776 Buick Ignition Retard Request Duration Fault

P1777 Buick Ignition Retard Request Circuit Fault

Possible causes
– Step Motor harness is open or shorted
– Step Motor poor electrical connection
– Faulty Step Motor
P1777 Buick Description

The step motor changes the step with turning 4 coils ON/OFF according to the signal from Transmission Control Module (TCM). As a result, the flow of line pressure to primary pulley is changed and pulley ratio is controlled

Buick Vehicle:Buick Regal – ?Buick Riviera – ?Buick LaCrosse – ?David Dunbar Buick – Buick Century – Buick LaCrosse – Buick LeSabre – Buick Lucerne – Buick Park Avenue – Buick Regal – Buick Verano – Buick Enclave – Buick Encore – Buick Rainier – Buick Rendezvous – Buick Terraza – Buick Riviera