Skip the auto shop - Our mechanics make house calls

P0827 OBD-II Trouble Code: Up and Down Shift Switch Input Circuit Low

diagnostic check engine light

P0827 code definition

The P0827 trouble code detects an electrical issue with the up and down shift switch circuit.

What the P0827 code means

The P0827 code is a generic OBD-II trouble code that notes an electrical problem with the upshift/downshift switch circuit, which contains the upshift/downshift switch, the mode actuator, and many electrical components. The upshift/downshift switch is used by the driver to control gears and shifting in an automatic transmission that has manual mode. When the powertrain control module (PCM) notes that the upshift/downshift switch circuit is producing an abnormal voltage or resistance signal, the P0827 trouble code will be detected.

What causes the P0827 code?

The P0827 trouble code is most frequently caused by damage to the upshift/downshift switch, which is located in the cabin of the vehicle, usually on the shifter, but sometimes on the steering wheel or column. This damage is usually the result of spilled liquids. Damaged electrical components (such as the wires and connectors) in the system can also trigger the P0827 code.

What are the symptoms of the P0827 code?

When the P0827 trouble code is detected, the check engine soon warning light will likely illuminate on the instrument cluster, though not always. It is common for the overdrive light to flash as well. As far as drivability is concerned, the manual mode in the automatic transmission will be disarmed, and the transmission may enter “limp-in” mode, which will impact the smoothness of the shifting.

How does a mechanic diagnose the P0827 code?

The P0827 code will be diagnosed using a standard OBD-II trouble code scanner. A professional technician will use the scanner to observe the freeze frame data, to gather information about the code. The mechanic will also check to see if additional trouble codes are present. If there are multiple codes, then they should be addressed in the order in which they appear on the scanner. The mechanic will then reset the trouble codes, restart the vehicle, and check to see if the code remains detected. If it does not, then the code was likely triggered erroneously, or represents an intermittent issue.

If the P0827 trouble code remains detected, then the mechanic should undergo a visual inspection of the electronical components in the automatic transmission. Any open or shorted wires, or damaged or corroded connectors should be replaced (it is also common for the entire electrical harness to be replaced). Next, the upshift/downshift switch will need to be carefully inspected, and quite likely replaced.

If the problem has not been found, the reference voltage and ground signals should be checked, and a digital volt/ohmmeter can be used to test for resistance and continuity between all the circuits.

After any component is replaced, the mechanic will reset the trouble codes, restart the vehicle, and once again check to see if the codes return. By doing this, the technician will be able to identify as soon as the issue has been resolved.

Common mistakes when diagnosing the P0827 code

The mistake that is made most often when diagnosing the P0827 code is the failure to properly comply with the OBD-II trouble code diagnosis protocol. Technicians should abide by the protocol step by step, at all times, to guarantee that every repair is both thorough and efficient.

It is fairly common for damaged switches to go unnoticed, because liquid spills do not always leave physical signs of damage.

How serious is the P0827 code?

A vehicle with a detected P0827 trouble code will still be drivable, though the manual shift mode may be deactivated, and shifting may be a little harsh. If this code is not resolved, further damage can occur to the transmission, so the P0827 code should be addressed as soon as it is detected.

What repairs can fix the P0827 code?

The most common repairs for the P0827 code are a replacement of the upshift/downshift switch, and replacement of the electrical components. In very rare cases, the PCM may need to be replaced.

Additional comments for consideration regarding the P0827 code

The P0827 trouble code only applies to vehicles that have automatic transmissions with manual shift mode.

Need help with a P0827 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...
How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...


Related questions

Q: Check Engine Light trouble code P0302. I changed the coil and switched plugs. This 2007 Corolla only has 26,000 miles. Is there an easy solution?

Diagnostic Trouble Code P0302 is not necessarily caused by a bad coil or spark plug. Unless the coil was actually tested, it could very well be perfectly good. Diagnostic Trouble Codes do not conclusively identify faulty parts. The only way...

Q: Looking for info about most common OBD2 Codes

There are two (at least) quite distinct issues in regard to your general request: The first is, once a check engine light illuminates, what are the most "frequent" codes that are stored and thence downloaded, that is what does THAT...

Q: engine wont restart when hot, no spark P0340 has 12v on both connectors, freq from 5-11hz when cranking

Since the crank position sensor gets its timing signal off the damper, I would first replace the damper to be sure timing was correct. The fact that this failure occurs after a "heat soak" cycle, and the P0340 code is...