Honda P0847 Code and the D Light is Flashing: Test and Fix

Diagnose and fix a Honda P0847 Code and a flashing D light

If you have a Honda P0847 code and the D light is flashing,  here is the diagnostic procedure. A P0847 is defined as a transmission fluid pressure switch B (3rd clutch) circuit that is low.

3rd clutch pressure switch

Locate the 3rd clutch pressure switch connector on the front of the transmission. It is a 1-wire blue connector. Back probe the blue/white wire in the connector and drive the vehicle. You should see voltage until the transmission is commanded to switch into 3rd gear. The 3rd gear switch should then ground, resulting in a significant voltage drop.

If you don’t see voltage on this wire, unplug the connector and check again. If you now see voltage, that’s an indication that the 3rd clutch switch has failed in the ON position where it is grounding the circuit full time. In that case, replace the 3rd clutch switch and that should eliminate the Honda P0847 code.

©, 2020 Rick Muscoplat