P2776 OBD-II Trouble Code: Upshift Switch Circuit Low

check engine light

P2776 code definition

If the PCM of your vehicle stores the P2776 code, it’s because it received feedback about a malfunction in the upshift switch circuit’s electrical circuit.

What the P2776 code means

Upshift switches are used on vehicles that have manually shifting automatic transmissions. It is installed close to the shifter located in the passenger compartment. The shift, connectors and system wiring and mode actuator are all part of the circuit.

If the PCM receives a resistance or voltage signal from the upshift switch circuit that falls outside of the manufacturer’s recommended specifications, the P2776 code will be stored and a Check Engine Light will most likely come on. Depending on your make and model, though, it may take several failure cycles before the light will be displayed. Sometimes, the light doesn’t come on at all.

What causes the P2776 code?

The P2776 code is usually caused by one of the following:

Both issues are often caused by spilled liquids reaching the upshift/downshift switch.

What are the symptoms of the P2776 code?

If your vehicle’s PCM stores a P2776 code, the manual shifter function should become disabled. Your transmission may also be put into limp-in mode by your transmission controller. This means that your vehicle will be limited to very low RPMs (hence “limping”). The idea is that it won’t be able to overheat or do further damage this way until repairs happen. Your transmission will still limp harshly, though, and torque converter lockup will most likely be impossible. You may also see the overdrive light flashing.

That being said, some people have reported no distinguishable symptoms associated with the P2776 code. Therefore, it may be extremely noticeable – in the cases listed above – or you may receive little more than a Check Engine Light.

How does a mechanic diagnose the P2776 code?

To diagnose the problem with your vehicle, a qualified mechanic will use both a digital ohmmeter and a code reader. Once they have the codes your vehicle’s PCM has stored, they’ll move onto examine the wiring and connectors for any signs of a problem. Then they’ll do the same with the internal transmission harness.

After getting the code to clear, the mechanic will take your vehicle for a quick test drive to see if the problem has been solved or if an intermittent condition may be to blame.

Common mistakes when diagnosing the P2776 code

A big mistake that occurs when trying to repair the problems which can trigger the P2776 code is that mechanics will go right to the transmission and start checking the wiring. There’s nothing wrong with this, of course, but when they give this preference over looking for spilled liquids, their attempts at repairs may fall short.

How serious is the P2776 code?

The P2776 code is far from the most serious code your PCM could store, but that doesn’t mean you should wait to have it addressed. Driving can become extremely inconvenient and you could even do further damage if you try pushing your transmission too far.

What repairs can fix the P2776 code?

Fortunately, fixing the P2766 code shouldn’t involve much more than simply trading out wires and other electrical elements that are no longer working properly.

The P2776 code can be repaired by:

  • Fixing/replacing any electrical components that aren’t working correctly because they’ve been damaged.

  • Looking for an internal source of liquid spilling and addressing it

  • In rare cases, dealing with a defective PCM

Additional comments for consideration regarding the P2776 code

As we touched on above, it’s so important to really look for where liquid could have spilled and spilled from. It might not be immediately apparent during a quick scan. Switches in the transmission, for example, make it very easy for signs of spilled fluid to hide.

Need help with a P2776 code?

If you need help with problems related to a stored P2776, YourMechanic is available to help. Just give us a call at 1-800-701-6230 to speak with one of our service advisors. You can also fill out our online form. Either way, we’ll get you a quote right away and schedule an appointment with one of our certified mobile mechanics.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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