P2780: Downshift Switch Circuit Low OBD-II Trouble Code

A downshift switch allows you to manually downshift the transmission by tapping the gear shift selector or one of the paddles behind the steering wheel. If there is a low voltage signal coming from the downshift switch circuit, a P2780 DTC will be saved in the ECU memory.

Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.

What Transmission Do I Have?

How Serious is the Code?

Although you won’t be able to manually downshift your transmission, a P2780 diagnostic trouble code is not likely to affect the drivability of your vehicle.

Symptoms

Symptoms of a P2780 include:

  • Manual shift gate and paddle shifters won’t work

Causes

  • Downshift switch failure
  • Wiring issue
  • Shifter assembly failure
  • ECU programming issue

How to Diagnose the Code?

If you want to figure out what is causing a P2780 trouble code, the wiring and connectors going to the shifter assembly will need to be checked for signs of damage and corrosion. The manufacturer’s database of TSB’s. (Technical Service Bulletins) is a great resource to see if there are any known solutions for this problem. If nothing is found, then the downshift switch and possibly the shifter assembly will need to be tested.

Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.

What Transmission Do I Have?

What Repairs Will Fix P2780?

  • Replace downshift switch
  • Repair wiring/connectors
  • Repair/replace shifter assembly
  • Reflash/update ECU programming

Related Codes

N/A