Honda P0847 D light flashing

Diagnose and fix Honda P0847 D light flashing

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

Locate the 3rd clutch pressure switch connector on the front of the transmission. It is a 1-wire blue connector. Backprobe the blue/white wire in the connector and driver 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.

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