P1787 Transmission 2-1 Downshift Error

Category: Powertrain - Transmission
Severity: Check Engine Light
Applies to: F-150, Explorer, Ranger

What does P1787 mean on a Ford?

P1787 — Transmission 2-1 Downshift Error. This Ford-enhanced code applies to F-150, Explorer, Ranger.

Common causes of P1787

Worn 2-1 downshift components
Failing solenoid
Valve body timing wear
Low line pressure
Low fluid level

How to fix P1787

Check fluid level and condition
Feel the 2-1 downshift on coast-down
Monitor timing data
Test solenoid operation
Service per findings